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is-link">Go</button> </div> </div> </form> </div> </div> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous is-invisible">Previous </a> <a href="/search/?searchtype=author&query=Jia%2C+Q&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Jia%2C+Q&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Jia%2C+Q&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> </ul> </nav> <ol class="breathe-horizontal" start="1"> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2411.12392">arXiv:2411.12392</a> <span> [<a href="https://arxiv.org/pdf/2411.12392">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Fluid Dynamics">physics.flu-dyn</span> </div> </div> <p class="title is-5 mathjax"> Extended Buoyancy-Drag Model for Ablative Rayleigh-Taylor Instability Seeded by Various Perturbations </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Liu%2C+D">Dongxue Liu</a>, <a href="/search/physics?searchtype=author&query=Tao%2C+T">Tao Tao</a>, <a href="/search/physics?searchtype=author&query=Li%2C+J">Jun Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+R">Rui Yan</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2411.12392v1-abstract-short" style="display: inline;"> In inertial confinement fusion (ICF), affected by non-steady ablation and various physical mechanisms, we extend the classical buoyancy-drag (BD) model into an ablative version for evaluating and controlling nonlinear ablative Rayleigh-Taylor instability (ARTI) in real space. The application of our ablative BD model in the nonlinear phase lies in a single adjustable coefficient influenced by initi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.12392v1-abstract-full').style.display = 'inline'; document.getElementById('2411.12392v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2411.12392v1-abstract-full" style="display: none;"> In inertial confinement fusion (ICF), affected by non-steady ablation and various physical mechanisms, we extend the classical buoyancy-drag (BD) model into an ablative version for evaluating and controlling nonlinear ablative Rayleigh-Taylor instability (ARTI) in real space. The application of our ablative BD model in the nonlinear phase lies in a single adjustable coefficient influenced by initial perturbations, linear growth rate and terminal velocity. After validating the effectiveness and sensitivity of this model through simulations, we propose a strategy to shift the dominant mode away from the "most dangerous mode", which depends on initial perturbations. Our findings suggest that the "most dangerous mode" may clarify gain differences among targets of similar qualities and provide guidance for target manufacturing and pulse optimization in proximity to the ignition cliff. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.12392v1-abstract-full').style.display = 'none'; document.getElementById('2411.12392v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2407.07651">arXiv:2407.07651</a> <span> [<a href="https://arxiv.org/pdf/2407.07651">pdf</a>, <a href="https://arxiv.org/format/2407.07651">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Physics - Experiment">hep-ex</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Data Analysis, Statistics and Probability">physics.data-an</span> </div> </div> <p class="title is-5 mathjax"> Study of the decay and production properties of $D_{s1}(2536)$ and $D_{s2}^*(2573)$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Ablikim%2C+M">M. Ablikim</a>, <a href="/search/physics?searchtype=author&query=Achasov%2C+M+N">M. N. Achasov</a>, <a href="/search/physics?searchtype=author&query=Adlarson%2C+P">P. Adlarson</a>, <a href="/search/physics?searchtype=author&query=Afedulidis%2C+O">O. Afedulidis</a>, <a href="/search/physics?searchtype=author&query=Ai%2C+X+C">X. C. Ai</a>, <a href="/search/physics?searchtype=author&query=Aliberti%2C+R">R. Aliberti</a>, <a href="/search/physics?searchtype=author&query=Amoroso%2C+A">A. Amoroso</a>, <a href="/search/physics?searchtype=author&query=An%2C+Q">Q. An</a>, <a href="/search/physics?searchtype=author&query=Bai%2C+Y">Y. Bai</a>, <a href="/search/physics?searchtype=author&query=Bakina%2C+O">O. Bakina</a>, <a href="/search/physics?searchtype=author&query=Balossino%2C+I">I. Balossino</a>, <a href="/search/physics?searchtype=author&query=Ban%2C+Y">Y. Ban</a>, <a href="/search/physics?searchtype=author&query=Bao%2C+H+-">H. -R. Bao</a>, <a href="/search/physics?searchtype=author&query=Batozskaya%2C+V">V. Batozskaya</a>, <a href="/search/physics?searchtype=author&query=Begzsuren%2C+K">K. Begzsuren</a>, <a href="/search/physics?searchtype=author&query=Berger%2C+N">N. Berger</a>, <a href="/search/physics?searchtype=author&query=Berlowski%2C+M">M. Berlowski</a>, <a href="/search/physics?searchtype=author&query=Bertani%2C+M">M. Bertani</a>, <a href="/search/physics?searchtype=author&query=Bettoni%2C+D">D. Bettoni</a>, <a href="/search/physics?searchtype=author&query=Bianchi%2C+F">F. Bianchi</a>, <a href="/search/physics?searchtype=author&query=Bianco%2C+E">E. Bianco</a>, <a href="/search/physics?searchtype=author&query=Bortone%2C+A">A. Bortone</a>, <a href="/search/physics?searchtype=author&query=Boyko%2C+I">I. Boyko</a>, <a href="/search/physics?searchtype=author&query=Briere%2C+R+A">R. A. Briere</a>, <a href="/search/physics?searchtype=author&query=Brueggemann%2C+A">A. Brueggemann</a> , et al. (645 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2407.07651v1-abstract-short" style="display: inline;"> The $e^+e^-\rightarrow D_s^+D_{s1}(2536)^-$ and $e^+e^-\rightarrow D_s^+D^*_{s2}(2573)^-$ processes are studied using data samples collected with the BESIII detector at center-of-mass energies from 4.530 to 4.946~GeV. The absolute branching fractions of $D_{s1}(2536)^- \rightarrow \bar{D}^{*0}K^-$ and $D_{s2}^*(2573)^- \rightarrow \bar{D}^0K^-$ are measured for the first time to be… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.07651v1-abstract-full').style.display = 'inline'; document.getElementById('2407.07651v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2407.07651v1-abstract-full" style="display: none;"> The $e^+e^-\rightarrow D_s^+D_{s1}(2536)^-$ and $e^+e^-\rightarrow D_s^+D^*_{s2}(2573)^-$ processes are studied using data samples collected with the BESIII detector at center-of-mass energies from 4.530 to 4.946~GeV. The absolute branching fractions of $D_{s1}(2536)^- \rightarrow \bar{D}^{*0}K^-$ and $D_{s2}^*(2573)^- \rightarrow \bar{D}^0K^-$ are measured for the first time to be $(35.9\pm 4.8\pm 3.5)\%$ and $(37.4\pm 3.1\pm 4.6)\%$, respectively. The measurements are in tension with predictions based on the assumption that the $D_{s1}(2536)$ and $D_{s2}^*(2573)$ are dominated by a bare $c\bar{s}$ component. The $e^+e^-\rightarrow D_s^+D_{s1}(2536)^-$ and $e^+e^-\rightarrow D_s^+D^*_{s2}(2573)^-$ cross sections are measured, and a resonant structure at around 4.6~GeV with a width of 50~MeV is observed for the first time with a statistical significance of $15蟽$ in the $e^+e^-\rightarrow D_s^+D^*_{s2}(2573)^-$ process. It could be the $Y(4626)$ found by the Belle collaboration in the $D_s^+D_{s1}(2536)^{-}$ final state, since they have similar masses and widths. There is also evidence for a structure at around 4.75~GeV in both processes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.07651v1-abstract-full').style.display = 'none'; document.getElementById('2407.07651v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 10 July, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2405.14735">arXiv:2405.14735</a> <span> [<a href="https://arxiv.org/pdf/2405.14735">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Generalized all-optical complex exponential operator </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Chen%2C+B">Baiqiao Chen</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi Jia</a>, <a href="/search/physics?searchtype=author&query=Feng%2C+R">Rui Feng</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+F">Fangkui Sun</a>, <a href="/search/physics?searchtype=author&query=Cao%2C+Y">Yongyin Cao</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+J">Jian Wang</a>, <a href="/search/physics?searchtype=author&query=Ding%2C+W">Weiqiang Ding</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2405.14735v1-abstract-short" style="display: inline;"> Euler's formula, an extraordinary mathematical formula, establishes a vital link between complex-valued operations and trigonometric functions, finding widespread application in various fields. With the end of Moore's Law, electronic computing methods are encountering developmental bottlenecks. With its enviable potential, optical computing has successfully achieved high-speed operation of designe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.14735v1-abstract-full').style.display = 'inline'; document.getElementById('2405.14735v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2405.14735v1-abstract-full" style="display: none;"> Euler's formula, an extraordinary mathematical formula, establishes a vital link between complex-valued operations and trigonometric functions, finding widespread application in various fields. With the end of Moore's Law, electronic computing methods are encountering developmental bottlenecks. With its enviable potential, optical computing has successfully achieved high-speed operation of designed complex numbers. However, the challenge of processing and manipulating arbitrary complex numbers persists. This study introduces a generalized complex exponential operator (GCEO), utilizing a diffractive optical neural network (DONN) for the computation of the complex exponential through Euler's formula. Experiments validate a series of complex exponential calculations using the GCEO. The GCEO has demonstrated generalizability and can compute inputs of any precision within an appropriate error margin. The proposed operator highlights the immense potential of DONN in optical computation and is poised to significantly contribute to the development of computational methods for optoelectronic integration. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.14735v1-abstract-full').style.display = 'none'; document.getElementById('2405.14735v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">17 pages, 4 figures, 1 table</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2405.13711">arXiv:2405.13711</a> <span> [<a href="https://arxiv.org/pdf/2405.13711">pdf</a>, <a href="https://arxiv.org/format/2405.13711">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Machine Learning">cs.LG</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Artificial Intelligence">cs.AI</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Dynamical Systems">math.DS</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Atmospheric and Oceanic Physics">physics.ao-ph</span> </div> </div> <p class="title is-5 mathjax"> VAE-Var: Variational-Autoencoder-Enhanced Variational Assimilation </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Xiao%2C+Y">Yi Xiao</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qilong Jia</a>, <a href="/search/physics?searchtype=author&query=Xue%2C+W">Wei Xue</a>, <a href="/search/physics?searchtype=author&query=Bai%2C+L">Lei Bai</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2405.13711v1-abstract-short" style="display: inline;"> Data assimilation refers to a set of algorithms designed to compute the optimal estimate of a system's state by refining the prior prediction (known as background states) using observed data. Variational assimilation methods rely on the maximum likelihood approach to formulate a variational cost, with the optimal state estimate derived by minimizing this cost. Although traditional variational meth… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.13711v1-abstract-full').style.display = 'inline'; document.getElementById('2405.13711v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2405.13711v1-abstract-full" style="display: none;"> Data assimilation refers to a set of algorithms designed to compute the optimal estimate of a system's state by refining the prior prediction (known as background states) using observed data. Variational assimilation methods rely on the maximum likelihood approach to formulate a variational cost, with the optimal state estimate derived by minimizing this cost. Although traditional variational methods have achieved great success and have been widely used in many numerical weather prediction centers, they generally assume Gaussian errors in the background states, which limits the accuracy of these algorithms due to the inherent inaccuracies of this assumption. In this paper, we introduce VAE-Var, a novel variational algorithm that leverages a variational autoencoder (VAE) to model a non-Gaussian estimate of the background error distribution. We theoretically derive the variational cost under the VAE estimation and present the general formulation of VAE-Var; we implement VAE-Var on low-dimensional chaotic systems and demonstrate through experimental results that VAE-Var consistently outperforms traditional variational assimilation methods in terms of accuracy across various observational settings. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.13711v1-abstract-full').style.display = 'none'; document.getElementById('2405.13711v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2404.07458">arXiv:2404.07458</a> <span> [<a href="https://arxiv.org/pdf/2404.07458">pdf</a>, <a href="https://arxiv.org/format/2404.07458">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> </div> <p class="title is-5 mathjax"> I-mode Plasma Confinement Improvement by Real-time Lithium Injection and its Classification on EAST Tokamak </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhong%2C+X+M">X. M. Zhong</a>, <a href="/search/physics?searchtype=author&query=Zou%2C+X+L">X. L. Zou</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+A+D">A. D. Liu</a>, <a href="/search/physics?searchtype=author&query=Song%2C+Y+T">Y. T. Song</a>, <a href="/search/physics?searchtype=author&query=Zhuang%2C+G">G. Zhuang</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+H+Q">H. Q. Liu</a>, <a href="/search/physics?searchtype=author&query=Xu%2C+L+Q">L. Q. Xu</a>, <a href="/search/physics?searchtype=author&query=Li%2C+E+Z">E. Z. Li</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+B">B. Zhang</a>, <a href="/search/physics?searchtype=author&query=Zuo%2C+G+Z">G. Z. Zuo</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+Z">Z. Wang</a>, <a href="/search/physics?searchtype=author&query=Zhou%2C+C">C. Zhou</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+J">J. Zhang</a>, <a href="/search/physics?searchtype=author&query=Shi%2C+W+X">W. X. Shi</a>, <a href="/search/physics?searchtype=author&query=Gao%2C+L+T">L. T. Gao</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+S+F">S. F. Wang</a>, <a href="/search/physics?searchtype=author&query=Gao%2C+W">W. Gao</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+T+Q">T. Q. Jia</a>, <a href="/search/physics?searchtype=author&query=Zang%2C+Q">Q. Zang</a>, <a href="/search/physics?searchtype=author&query=Zhao%2C+H+L">H. L. Zhao</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+M">M. Wang</a>, <a href="/search/physics?searchtype=author&query=Xu%2C+H+D">H. D. Xu</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+X+J">X. J. Wang</a>, <a href="/search/physics?searchtype=author&query=Gao%2C+X">X. Gao</a>, <a href="/search/physics?searchtype=author&query=Lin%2C+X+D">X. D. Lin</a> , et al. (3 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2404.07458v1-abstract-short" style="display: inline;"> I-mode is a promising regime for future fusion reactors due to the high energy confinement and the moderate particle confinement. However, the effect of lithium, which has been widely applied for particle recycling and impurity control, on I-mode plasma is still unclear. Recently, experiments of real-time lithium powder injection on I-mode plasma have been carried out in EAST Tokamak. It was found… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2404.07458v1-abstract-full').style.display = 'inline'; document.getElementById('2404.07458v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2404.07458v1-abstract-full" style="display: none;"> I-mode is a promising regime for future fusion reactors due to the high energy confinement and the moderate particle confinement. However, the effect of lithium, which has been widely applied for particle recycling and impurity control, on I-mode plasma is still unclear. Recently, experiments of real-time lithium powder injection on I-mode plasma have been carried out in EAST Tokamak. It was found that the confinement performance of the I-mode can be improved by the lithium powder injection, which can strongly reduce electron turbulence (ET) and then trigger ion turbulence (IT). Four different regimes of I-mode have been identified in EAST. The Type I I-mode plasma is characterized by the weakly coherent mode (WCM) and the geodesic-acoustic mode (GAM). The Type II I-mode is featured as the WCM and the edge temperature ring oscillation (ETRO). The Type III I-mode corresponds to the plasma with the co-existence of ETRO, GAM, and WCM. The Type IV I-mode denotes the plasma with only WCM but without ETRO and GAM. It has been observed that WCM and ETRO are increased with lithium powder injection due to the reduction of ion and electron turbulence, and the enhancement of the pedestal electron temperature gradient. EAST experiments demonstrate that lithium powder injection is an effective tool for real-time control and confinement improvement of I-mode plasma. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2404.07458v1-abstract-full').style.display = 'none'; document.getElementById('2404.07458v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 10 April, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2307.00192">arXiv:2307.00192</a> <span> [<a href="https://arxiv.org/pdf/2307.00192">pdf</a>, <a href="https://arxiv.org/ps/2307.00192">ps</a>, <a href="https://arxiv.org/format/2307.00192">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> </div> <p class="title is-5 mathjax"> Generation of intense cylindrical vector beams by Faraday effect in plasma </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Liu%2C+W">Wei Liu</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2307.00192v1-abstract-short" style="display: inline;"> Cylindrical vector (CV) beams, whose polarizations are cylindrically symmetric, have recently been widely applied in high energy density physics such as electron acceleration and intense spatiotemporal optical vortices generation. Thermal-damage-resistant plasma optics are expected to generate intense CV beams. In this work, based on the Faraday effect, we propose a method that can directly conver… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.00192v1-abstract-full').style.display = 'inline'; document.getElementById('2307.00192v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2307.00192v1-abstract-full" style="display: none;"> Cylindrical vector (CV) beams, whose polarizations are cylindrically symmetric, have recently been widely applied in high energy density physics such as electron acceleration and intense spatiotemporal optical vortices generation. Thermal-damage-resistant plasma optics are expected to generate intense CV beams. In this work, based on the Faraday effect, we propose a method that can directly convert an intense linearly/circularly polarized Gaussian beam into a CV/vortex beam by setting up an azimuthally distributed axial magnetic field in the plasma. Three-dimensional particle-in-cell simulations demonstrate good conversion efficiency, which offers a new degree of freedom for manipulating high-power laser pulses and paves the way for further studies on ultra-strong vector beams. In addition, our work reveals a new possible source of photon orbital angular momentum related to magnetized plasma in astrophysics and space physics. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.00192v1-abstract-full').style.display = 'none'; document.getElementById('2307.00192v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 30 June, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2305.14895">arXiv:2305.14895</a> <span> [<a href="https://arxiv.org/pdf/2305.14895">pdf</a>, <a href="https://arxiv.org/format/2305.14895">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Physics - Experiment">hep-ex</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Instrumentation and Detectors">physics.ins-det</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-4527/acd593">10.1088/1674-4527/acd593 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Lobster Eye Imager for Astronomy Onboard the SATech-01 Satellite </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Ling%2C+Z+X">Z. X. Ling</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+X+J">X. J. Sun</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+C">C. Zhang</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+S+L">S. L. Sun</a>, <a href="/search/physics?searchtype=author&query=Jin%2C+G">G. Jin</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+S+N">S. N. Zhang</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+X+F">X. F. Zhang</a>, <a href="/search/physics?searchtype=author&query=Chang%2C+J+B">J. B. Chang</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+F+S">F. S. Chen</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+Y+F">Y. F. Chen</a>, <a href="/search/physics?searchtype=author&query=Cheng%2C+Z+W">Z. W. Cheng</a>, <a href="/search/physics?searchtype=author&query=Fu%2C+W">W. Fu</a>, <a href="/search/physics?searchtype=author&query=Han%2C+Y+X">Y. X. Han</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">H. Li</a>, <a href="/search/physics?searchtype=author&query=Li%2C+J+F">J. F. Li</a>, <a href="/search/physics?searchtype=author&query=Li%2C+Y">Y. Li</a>, <a href="/search/physics?searchtype=author&query=Li%2C+Z+D">Z. D. Li</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+P+R">P. R. Liu</a>, <a href="/search/physics?searchtype=author&query=Lv%2C+Y+H">Y. H. Lv</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+X+H">X. H. Ma</a>, <a href="/search/physics?searchtype=author&query=Tang%2C+Y+J">Y. J. Tang</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+C+B">C. B. Wang</a>, <a href="/search/physics?searchtype=author&query=Xie%2C+R+J">R. J. Xie</a>, <a href="/search/physics?searchtype=author&query=Xue%2C+Y+L">Y. L. Xue</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+A+L">A. L. Yan</a> , et al. (101 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2305.14895v1-abstract-short" style="display: inline;"> The Lobster Eye Imager for Astronomy (LEIA), a pathfinder of the Wide-field X-ray Telescope of the Einstein Probe (EP) mission, was successfully launched onboard the SATech-01 satellite of the Chinese Academy of Sciences on 27 July 2022. In this paper, we introduce the design and on-ground test results of the LEIA instrument. Using state-of-the-art Micro-Pore Optics (MPO), a wide field-of-view (Fo… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.14895v1-abstract-full').style.display = 'inline'; document.getElementById('2305.14895v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.14895v1-abstract-full" style="display: none;"> The Lobster Eye Imager for Astronomy (LEIA), a pathfinder of the Wide-field X-ray Telescope of the Einstein Probe (EP) mission, was successfully launched onboard the SATech-01 satellite of the Chinese Academy of Sciences on 27 July 2022. In this paper, we introduce the design and on-ground test results of the LEIA instrument. Using state-of-the-art Micro-Pore Optics (MPO), a wide field-of-view (FoV) of 346 square degrees (18.6 degrees * 18.6 degrees) of the X-ray imager is realized. An optical assembly composed of 36 MPO chips is used to focus incident X-ray photons, and four large-format complementary metal-oxide semiconductor (CMOS) sensors, each of 6 cm * 6 cm, are used as the focal plane detectors. The instrument has an angular resolution of 4 - 8 arcmin (in FWHM) for the central focal spot of the point spread function, and an effective area of 2 - 3 cm2 at 1 keV in essentially all the directions within the field of view. The detection passband is 0.5 - 4 keV in the soft X-rays and the sensitivity is 2 - 3 * 10-11 erg s-1 cm-2 (about 1 mini-Crab) at 1,000 second observation. The total weight of LEIA is 56 kg and the power is 85 W. The satellite, with a design lifetime of 2 years, operates in a Sun-synchronous orbit of 500 km with an orbital period of 95 minutes. LEIA is paving the way for future missions by verifying in flight the technologies of both novel focusing imaging optics and CMOS sensors for X-ray observation, and by optimizing the working setups of the instrumental parameters. In addition, LEIA is able to carry out scientific observations to find new transients and to monitor known sources in the soft X-ray band, albeit limited useful observing time available. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.14895v1-abstract-full').style.display = 'none'; document.getElementById('2305.14895v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 24 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted by RAA</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2305.06826">arXiv:2305.06826</a> <span> [<a href="https://arxiv.org/pdf/2305.06826">pdf</a>, <a href="https://arxiv.org/format/2305.06826">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Suppressing stimulated Raman side-scattering by vector light </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+X">Xiaobao Jia</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+R">Rui Yan</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2305.06826v1-abstract-short" style="display: inline;"> Recently, the verification of stimulated Raman side-scattering (SRSS) in different laser inertial confinement fusion ignition schemes poses an underlying risk of SRSS on ignition. In this paper, we propose a method to use the non-uniform polarization nature of vector light to suppress SRSS and give an additional threshold condition determined by the parameter of vector light. For SRSS at 90 degree… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.06826v1-abstract-full').style.display = 'inline'; document.getElementById('2305.06826v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.06826v1-abstract-full" style="display: none;"> Recently, the verification of stimulated Raman side-scattering (SRSS) in different laser inertial confinement fusion ignition schemes poses an underlying risk of SRSS on ignition. In this paper, we propose a method to use the non-uniform polarization nature of vector light to suppress SRSS and give an additional threshold condition determined by the parameter of vector light. For SRSS at 90 degrees, where the scattered electromagnetic wave travels perpendicular to the density profile, the polarization variation of the pump will change the wave vector of scattered light, thereby reducing the growth length and preventing the scattered electromagnetic wave from growing. This suppressive scheme is verified through three-dimensional particle-in-cell simulations. Our illustrative simulation results demonstrate that for linearly polarized Gaussian light, the SRSS signal occurs in the 90-degree direction fiercely. At the same time, for the vector light, there is few SRSS signal even if the condition dramatically exceeds the threshold. Furthermore, we discuss the impact of vector light on stimulated Raman and Brillouin backscattering, and two-plasma decay. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.06826v1-abstract-full').style.display = 'none'; document.getElementById('2305.06826v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages,5 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2302.11778">arXiv:2302.11778</a> <span> [<a href="https://arxiv.org/pdf/2302.11778">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.124535">10.1016/j.ijheatmasstransfer.2023.124535 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Differential Multi-probe Thermal Transport Measurements of Multi-walled Carbon Nanotubes grown by Chemical Vapor Deposition </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qianru Jia</a>, <a href="/search/physics?searchtype=author&query=Zhou%2C+Y">Yuanyuan Zhou</a>, <a href="/search/physics?searchtype=author&query=Li%2C+X">Xun Li</a>, <a href="/search/physics?searchtype=author&query=Lindsay%2C+L">Lucas Lindsay</a>, <a href="/search/physics?searchtype=author&query=Shi%2C+L">Li Shi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2302.11778v4-abstract-short" style="display: inline;"> Carbon nanotubes (CNTs) are quasi-1D nanostructures that display both high thermal conductivity and intriguing low-dimensional phonon transport phenomena. In comparison to the advances made in the theoretical calculation of the lattice thermal conductivity of CNTs, thermal transport measurements of CNTs have been limited by either the poor temperature sensitivity of Raman thermometry technique or… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.11778v4-abstract-full').style.display = 'inline'; document.getElementById('2302.11778v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2302.11778v4-abstract-full" style="display: none;"> Carbon nanotubes (CNTs) are quasi-1D nanostructures that display both high thermal conductivity and intriguing low-dimensional phonon transport phenomena. In comparison to the advances made in the theoretical calculation of the lattice thermal conductivity of CNTs, thermal transport measurements of CNTs have been limited by either the poor temperature sensitivity of Raman thermometry technique or the presence of contact thermal resistance errors in sensitive two-probe resistance thermometry measurements. Here we report advances in a multi-probe measurement of the intrinsic thermal conductivity of individual multi-walled CNT samples that are transferred from the growth substrate onto the measurement device. The sample-thermometer thermal interface resistance is directly measured by this multi-probe method and used to model the temperature distribution along the contacted sample segment. The detailed temperature profile helps to eliminate the contact thermal resistance error in the obtained thermal conductivity of the suspended sample segment. A differential electro-thermal bridge measurement method is established to enhance the signal-to-noise ratio and reduce the measurement uncertainty by over 40%. The obtained thermal resistances of multiple suspended segments of the same MWCNT sample increase linearly with increasing length, revealing diffusive phonon transport as a result of phonon-defect scattering in these MWCNTs. The measured thermal conductivity increases with temperature and reaches up to 390+- 20 W m-1 K-1 at room temperature for a 9-walled MWCNT. Theoretical analysis of the measurement results suggests submicron phonon mean free paths due to extrinsic phonon scattering by extended defects such as grain boundaries. The obtained thermal conductivity is decreased by a factor of 3 upon electron beam damage and surface contamination of the CNT sample. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.11778v4-abstract-full').style.display = 'none'; document.getElementById('2302.11778v4-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 31 July, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 22 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2212.11549">arXiv:2212.11549</a> <span> [<a href="https://arxiv.org/pdf/2212.11549">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Computational Physics">physics.comp-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1063/5.0142281">10.1063/5.0142281 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Prediction of surface reconstructions using MAGUS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Han%2C+Y">Yu Han</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+J">Junjie Wang</a>, <a href="/search/physics?searchtype=author&query=Ding%2C+C">Chi Ding</a>, <a href="/search/physics?searchtype=author&query=Gao%2C+H">Hao Gao</a>, <a href="/search/physics?searchtype=author&query=Pan%2C+S">Shuning Pan</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qiuhan Jia</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+J">Jian Sun</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2212.11549v1-abstract-short" style="display: inline;"> In this paper, we present a new module to predict the potential surface reconstruction configurations of given surface structures in the framework of our machine learning and graph theory assisted universal structure searcher (MAGUS). In addition to random structures generated with specific lattice symmetry, we made full use of bulk materials to obtain a better distribution of population energy, n… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.11549v1-abstract-full').style.display = 'inline'; document.getElementById('2212.11549v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2212.11549v1-abstract-full" style="display: none;"> In this paper, we present a new module to predict the potential surface reconstruction configurations of given surface structures in the framework of our machine learning and graph theory assisted universal structure searcher (MAGUS). In addition to random structures generated with specific lattice symmetry, we made full use of bulk materials to obtain a better distribution of population energy, namely, randomly appending atoms to a surface cleaved from bulk structures or moving/removing some of the atoms on the surface, which is inspired by natural surface reconstruction processes. In addition, we borrowed ideas from cluster predictions to spread structures better between different compositions, considering that surface models of different atom numbers usually have some building blocks in common. To validate this newly developed module, we tested it with studies on the surface reconstructions of Si (100), Si (111) and 4H-SiC(1-102)-c(2x2), respectively. We successfully gave the known ground states as well as a new SiC surface model in an extremely Si-rich environment. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.11549v1-abstract-full').style.display = 'none'; document.getElementById('2212.11549v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 December, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">20 pages, 5 figures. (Email: jiansun@nju.edu.cn)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2212.08825">arXiv:2212.08825</a> <span> [<a href="https://arxiv.org/pdf/2212.08825">pdf</a>, <a href="https://arxiv.org/format/2212.08825">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1515/nanoph-2023-0482">10.1515/nanoph-2023-0482 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Simultaneously sorting vector vortex beams of 120 modes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi Jia</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+Y">Yanxia Zhang</a>, <a href="/search/physics?searchtype=author&query=Shi%2C+B">Bojian Shi</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">Hang Li</a>, <a href="/search/physics?searchtype=author&query=Li%2C+X">Xiaoxin Li</a>, <a href="/search/physics?searchtype=author&query=Feng%2C+R">Rui Feng</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+F">Fangkui Sun</a>, <a href="/search/physics?searchtype=author&query=Cao%2C+Y">Yongyin Cao</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+J">Jian Wang</a>, <a href="/search/physics?searchtype=author&query=Qiu%2C+C">Cheng-Wei Qiu</a>, <a href="/search/physics?searchtype=author&query=Ding%2C+W">Weiqiang Ding</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2212.08825v1-abstract-short" style="display: inline;"> Polarization (P), angular index (l), and radius index (p) are three independent degrees of freedom (DoFs) of vector vortex beams, which have been widely used in optical communications, quantum optics, information processing, etc. Although the sorting of one DoF can be achieved efficiently, it is still a great challenge to sort all these DoFs simultaneously in a compact and efficient way. Here, we… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.08825v1-abstract-full').style.display = 'inline'; document.getElementById('2212.08825v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2212.08825v1-abstract-full" style="display: none;"> Polarization (P), angular index (l), and radius index (p) are three independent degrees of freedom (DoFs) of vector vortex beams, which have been widely used in optical communications, quantum optics, information processing, etc. Although the sorting of one DoF can be achieved efficiently, it is still a great challenge to sort all these DoFs simultaneously in a compact and efficient way. Here, we propose a beam sorter to deal with all these three DoFs simultaneously by using a diffractive deep neural network (D$^2$NN) and experimentally demonstrated the robust sorting of 120 Laguerre-Gaussian (LG) modes using a compact D$^2$NN formed by one spatial light modulator and one mirror only. The proposed beam sorter demonstrates the great potential of D$^2$NN in optical field manipulation and will benefit the diverse applications of vector vortex beams. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.08825v1-abstract-full').style.display = 'none'; document.getElementById('2212.08825v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 17 December, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2211.02803">arXiv:2211.02803</a> <span> [<a href="https://arxiv.org/pdf/2211.02803">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1016/j.actamat.2023.118782">10.1016/j.actamat.2023.118782 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ultralight and ultra-stiff nano-cardboard panels: mechanical analysis, characterization, and design principles </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Kim%2C+J">Jong-hyoung Kim</a>, <a href="/search/physics?searchtype=author&query=Jin%2C+L">Lishuai Jin</a>, <a href="/search/physics?searchtype=author&query=Schafer%2C+B+C">Benjamin C. Schafer</a>, <a href="/search/physics?searchtype=author&query=Jiao%2C+Q">Quan Jiao</a>, <a href="/search/physics?searchtype=author&query=Bertoldi%2C+K">Katia Bertoldi</a>, <a href="/search/physics?searchtype=author&query=Keith%2C+D+W">David W. Keith</a>, <a href="/search/physics?searchtype=author&query=Vlassak%2C+J+J">Joost J. Vlassak</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2211.02803v1-abstract-short" style="display: inline;"> We introduce a class of ultra-light and ultra-stiff sandwich panels designed for use in photophoretic levitation applications and investigate their mechanical behavior using both computational analyses and micro-mechanical testing. The sandwich panels consist of two face sheets connected with a core that consists of hollow cylindrical ligaments arranged in a honeycomb-based hexagonal pattern. Comp… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2211.02803v1-abstract-full').style.display = 'inline'; document.getElementById('2211.02803v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2211.02803v1-abstract-full" style="display: none;"> We introduce a class of ultra-light and ultra-stiff sandwich panels designed for use in photophoretic levitation applications and investigate their mechanical behavior using both computational analyses and micro-mechanical testing. The sandwich panels consist of two face sheets connected with a core that consists of hollow cylindrical ligaments arranged in a honeycomb-based hexagonal pattern. Computational modeling shows that the panels have superior bending stiffness and buckling resistance compared to similar panels with a basketweave core, and that their behavior is well described by Uflyand-Mindlin plate theory. By optimizing the ratio of the face sheet thickness to the ligament wall thickness, panels maybe obtained that have a bending stiffness that is more than five orders of magnitude larger than that of a solid plate with the same area density. Using a scalable microfabrication process, we demonstrate that panels as large as 3x3 cm^2 with a density of 20 kg/m^3 can be made in a few hours. Micro-mechanical testing of the panels is performed by deflecting microfabricated cantilevered panels using a nanoindenter. The experimentally measured bending stiffness of the cantilevered panels is in very good agreement with the computational results, demonstrating exquisite control over the dimensions, form, and properties of the microfabricated panels. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2211.02803v1-abstract-full').style.display = 'none'; document.getElementById('2211.02803v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 4 November, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Main: 26 pages, 10 figures. Supporting information: 5 pages, 4 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2210.02815">arXiv:2210.02815</a> <span> [<a href="https://arxiv.org/pdf/2210.02815">pdf</a>, <a href="https://arxiv.org/format/2210.02815">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1361-6587/acc420">10.1088/1361-6587/acc420 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Plasma zone plate for high-power lasers driven by a Laguerre-Gaussian beam </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Wang%2C+L">Lukai Wang</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+W">Wei Liu</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2210.02815v1-abstract-short" style="display: inline;"> Plasma-based optics has emerged as an attractive alternative to traditional solid-state optics for high-power laser manipulation due to its higher damage threshold. In this work, we propose a plasma zone plate (PZP) driven by the ponderomotive force of a Laguerre-Gaussian beam when it irradiates an underdense plasma slice. We formulate the theory of the PZP and demonstrate its formation and functi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.02815v1-abstract-full').style.display = 'inline'; document.getElementById('2210.02815v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2210.02815v1-abstract-full" style="display: none;"> Plasma-based optics has emerged as an attractive alternative to traditional solid-state optics for high-power laser manipulation due to its higher damage threshold. In this work, we propose a plasma zone plate (PZP) driven by the ponderomotive force of a Laguerre-Gaussian beam when it irradiates an underdense plasma slice. We formulate the theory of the PZP and demonstrate its formation and function of focusing high-power lasers using particle-in-cell simulations. The proposed scheme may offer a new method to focus and manipulate high-power lasers with plasma-based optics <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.02815v1-abstract-full').style.display = 'none'; document.getElementById('2210.02815v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 October, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2208.13120">arXiv:2208.13120</a> <span> [<a href="https://arxiv.org/pdf/2208.13120">pdf</a>, <a href="https://arxiv.org/format/2208.13120">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Computational Physics">physics.comp-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Explicit high-order symplectic integrators of coupled Schrodinger equations for pump-probe systems </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+X">Xiaobao Jia</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Xiao%2C+J">Jianyuan Xiao</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2208.13120v1-abstract-short" style="display: inline;"> Two-beam coupling within the field of nonlinear optics, which transfers energy from one light beam to the other under certain conditions, has received considerable attention in inertial confinement fusion (ICF) and plasma optics. To evaluate the coupling dynamics precisely, we modeled this process with full-wave coupled Schrodinger equations (CSEs) and a nonlinear refractive index. We found that t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.13120v1-abstract-full').style.display = 'inline'; document.getElementById('2208.13120v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2208.13120v1-abstract-full" style="display: none;"> Two-beam coupling within the field of nonlinear optics, which transfers energy from one light beam to the other under certain conditions, has received considerable attention in inertial confinement fusion (ICF) and plasma optics. To evaluate the coupling dynamics precisely, we modeled this process with full-wave coupled Schrodinger equations (CSEs) and a nonlinear refractive index. We found that the CSEs constituted a Hamiltonian system and proposed an arbitrary higher-order explicit symplectic algorithm to solve the CSEs numerically. The numerical results given by the developed BEAM code showed a good agreement with those from particle-in-cell simulations, which demonstrated the validity of the model and algorithm. The model and numerical algorithm presented in this work can be extended to more nonlinear optical interactions described by coupled-wave equations. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.13120v1-abstract-full').style.display = 'none'; document.getElementById('2208.13120v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 August, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">27 pages, 5 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2204.09208">arXiv:2204.09208</a> <span> [<a href="https://arxiv.org/pdf/2204.09208">pdf</a>, <a href="https://arxiv.org/ps/2204.09208">ps</a>, <a href="https://arxiv.org/format/2204.09208">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1361-6587/ac89ac">10.1088/1361-6587/ac89ac <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Optimizing doping parameters of target to enhance direct-drive implosion </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zheng%2C+G">Guannan Zheng</a>, <a href="/search/physics?searchtype=author&query=Tao%2C+T">Tao Tao</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+R">Rui Yan</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2204.09208v1-abstract-short" style="display: inline;"> Direct-drive is an important approach to achieving the ignition of inertial confinement fusion. To enhance implosion performance while keeping the risk of hydrodynamic instability at a low level, we have designed a procedure to optimize the parameters of the target doped with mid- or high-$Z$ atoms. In the procedure, a one-dimensional implosion can be automatically simulated, while its implosion p… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.09208v1-abstract-full').style.display = 'inline'; document.getElementById('2204.09208v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2204.09208v1-abstract-full" style="display: none;"> Direct-drive is an important approach to achieving the ignition of inertial confinement fusion. To enhance implosion performance while keeping the risk of hydrodynamic instability at a low level, we have designed a procedure to optimize the parameters of the target doped with mid- or high-$Z$ atoms. In the procedure, a one-dimensional implosion can be automatically simulated, while its implosion performance and high-dimensional instability are integrally evaluated at the same time. To find the optimal doping parameters, the procedure is performed in the framework of global optimization algorithm, where we have used the particle swarm optimization in the current work. In the optimization, the opacity of mixture materials is quickly obtained by using an interpolation method, showing only a slight difference from the data of TOPS, which is an online doping program of Los Alamos National Laboratory. To test the procedure, optimization has been carried out for the CH ablator in the double cone ignition scheme [Phil. Trans. R. Soc. A. 378.2184 (2020)] by doping with Si and Cl. Both one- and two-dimensional simulations show that doping with either Si or Cl can efficiently mitigate the instability during the acceleration phase and does not result in significant degradation of the peak areal density. The results from one- and two-dimensional simulations qualitatively match with each other, demonstrating the validity of our optimization procedure. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.09208v1-abstract-full').style.display = 'none'; document.getElementById('2204.09208v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2204.09203">arXiv:2204.09203</a> <span> [<a href="https://arxiv.org/pdf/2204.09203">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> </div> <p class="title is-5 mathjax"> Laser pulse shape designer for direct-drive inertial confinement fusion </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Tao%2C+T">Tao Tao</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+G">Guannan Zheng</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+R">Rui Yan</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">Jian Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2204.09203v2-abstract-short" style="display: inline;"> A pulse shape designer for direct drive inertial confinement fusion has been developed, it aims at high compression of the fusion fuel while keeping hydrodynamics instability within tolerable level. Fast linear analysis on implosion instability enables the designer to fully scan the vast pulse configuration space at a practical computational cost, machine learning helps to summarize pulse performa… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.09203v2-abstract-full').style.display = 'inline'; document.getElementById('2204.09203v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2204.09203v2-abstract-full" style="display: none;"> A pulse shape designer for direct drive inertial confinement fusion has been developed, it aims at high compression of the fusion fuel while keeping hydrodynamics instability within tolerable level. Fast linear analysis on implosion instability enables the designer to fully scan the vast pulse configuration space at a practical computational cost, machine learning helps to summarize pulse performance into an implicit scaling metric that promotes the pulse shape evolution. The designer improves its credibility by incorporating various datasets including extra high-precision simulations or experiments. When tested on the double-cone ignition scheme [J. Zhang et al, Phil. Trans. R. Soc. A. 378.2184 (2020)], optimized pulses reach the assembly requirements, show significant imprint mitigation and adiabatic shaping capability, and have the potential to achieve better implosion performance in real experiments. This designer serves as an efficient alternative to traditional empirical pulse shape tuning procedure, reduces workload and time consumption. The designer can be used to quickly explore the unknown parameter space for new direct-drive schemes, assists design iteration and reduces experiment risk. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.09203v2-abstract-full').style.display = 'none'; document.getElementById('2204.09203v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 8 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 19 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2204.08725">arXiv:2204.08725</a> <span> [<a href="https://arxiv.org/pdf/2204.08725">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1063/5.0096994">10.1063/5.0096994 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Mitigating laser imprint with a foam overcoating </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Liu%2C+D+X">D. X. Liu</a>, <a href="/search/physics?searchtype=author&query=Tao%2C+T">T. Tao</a>, <a href="/search/physics?searchtype=author&query=Li%2C+J">J. Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Q. Jia</a>, <a href="/search/physics?searchtype=author&query=Zheng%2C+J">J. Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2204.08725v1-abstract-short" style="display: inline;"> Foam has been suggested to reduce laser imprint because of its low density. In this paper, the two-dimensional radiation hydrodynamic code FLASH is applied to investigate and characterize the strength of laser imprint through analyzing areal density perturbation. There are two important factors for the mitigation of laser imprint besides the thermal smoothing of the conduction region (between the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.08725v1-abstract-full').style.display = 'inline'; document.getElementById('2204.08725v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2204.08725v1-abstract-full" style="display: none;"> Foam has been suggested to reduce laser imprint because of its low density. In this paper, the two-dimensional radiation hydrodynamic code FLASH is applied to investigate and characterize the strength of laser imprint through analyzing areal density perturbation. There are two important factors for the mitigation of laser imprint besides the thermal smoothing of the conduction region (between the ablation front and the critical density surface) and the mass ablation of the ablation front. First, radiation ablation dynamically modulates density distribution not only to increase the frequency of the perturbed ablation front oscillation but also to decrease the amplitude of oscillation. Second, a larger length of the shocked compression region reduces the amplitude of the perturbed shock front oscillation. The smaller the perturbation of both ablation front and shock front, the smaller the areal density perturbation. Based on the above physical mechanisms, the optimal way of mitigating laser imprint with foam is that the dynamically modulated density distribution further reduces the amplitude of perturbation reaching the solid CH when the areal density perturbation of foam oscillates to the first minimum value. The optimal ranges of foam parameters to mitigate laser imprint are proposed with the aid of dimensional analysis: the foam thickness is about 2~3 times the perturbation wavelength, and the foam density is about 1/2~3/2 times the mass density corresponding to the critical density. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2204.08725v1-abstract-full').style.display = 'none'; document.getElementById('2204.08725v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2202.09460">arXiv:2202.09460</a> <span> [<a href="https://arxiv.org/pdf/2202.09460">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Chemical Physics">physics.chem-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> </div> <p class="title is-5 mathjax"> Atomic-scale identification of the active sites of nanocatalysts </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Yang%2C+Y">Yao Yang</a>, <a href="/search/physics?searchtype=author&query=Zhou%2C+J">Jihan Zhou</a>, <a href="/search/physics?searchtype=author&query=Zhao%2C+Z">Zipeng Zhao</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+G">Geng Sun</a>, <a href="/search/physics?searchtype=author&query=Moniri%2C+S">Saman Moniri</a>, <a href="/search/physics?searchtype=author&query=Ophus%2C+C">Colin Ophus</a>, <a href="/search/physics?searchtype=author&query=Yang%2C+Y">Yongsoo Yang</a>, <a href="/search/physics?searchtype=author&query=Wei%2C+Z">Ziyang Wei</a>, <a href="/search/physics?searchtype=author&query=Yuan%2C+Y">Yakun Yuan</a>, <a href="/search/physics?searchtype=author&query=Zhu%2C+C">Cheng Zhu</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+Q">Qiang Sun</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qingying Jia</a>, <a href="/search/physics?searchtype=author&query=Heinz%2C+H">Hendrik Heinz</a>, <a href="/search/physics?searchtype=author&query=Ciston%2C+J">Jim Ciston</a>, <a href="/search/physics?searchtype=author&query=Ercius%2C+P">Peter Ercius</a>, <a href="/search/physics?searchtype=author&query=Sautet%2C+P">Philippe Sautet</a>, <a href="/search/physics?searchtype=author&query=Huang%2C+Y">Yu Huang</a>, <a href="/search/physics?searchtype=author&query=Miao%2C+J">Jianwei Miao</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2202.09460v1-abstract-short" style="display: inline;"> Alloy nanocatalysts have found broad applications ranging from fuel cells to catalytic converters and hydrogenation reactions. Despite extensive studies, identifying the active sites of nanocatalysts remains a major challenge due to the heterogeneity of the local atomic environment. Here, we advance atomic electron tomography to determine the 3D local atomic structure, surface morphology and chemi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2202.09460v1-abstract-full').style.display = 'inline'; document.getElementById('2202.09460v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2202.09460v1-abstract-full" style="display: none;"> Alloy nanocatalysts have found broad applications ranging from fuel cells to catalytic converters and hydrogenation reactions. Despite extensive studies, identifying the active sites of nanocatalysts remains a major challenge due to the heterogeneity of the local atomic environment. Here, we advance atomic electron tomography to determine the 3D local atomic structure, surface morphology and chemical composition of PtNi and Mo-doped PtNi nanocatalysts. Using machine learning trained by density functional theory calculations, we identify the catalytic active sites for the oxygen reduction reaction from experimental 3D atomic coordinates, which are corroborated by electrochemical measurements. By quantifying the structure-activity relationship, we discover a local environment descriptor to explain and predict the catalytic active sites at the atomic level. The ability to determine the 3D atomic structure and chemical species coupled with machine learning is expected to expand our fundamental understanding of a wide range of nanocatalysts. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2202.09460v1-abstract-full').style.display = 'none'; document.getElementById('2202.09460v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 February, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">37 pages, 16 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2201.03855">arXiv:2201.03855</a> <span> [<a href="https://arxiv.org/pdf/2201.03855">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.37188/lam.2022.045">10.37188/lam.2022.045 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Plug-Play Plasmonic Metafibers for Ultrafast Fiber Lasers </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhang%2C+L">Lei Zhang</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+H">Huiru Zhang</a>, <a href="/search/physics?searchtype=author&query=Tang%2C+N">Ni Tang</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+X">Xiren Chen</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+F">Fengjiang Liu</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+X">Xiaoyu Sun</a>, <a href="/search/physics?searchtype=author&query=Yu%2C+H">Hongyan Yu</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+X">Xinyu Sun</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qiannan Jia</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+B">Boqu Chen</a>, <a href="/search/physics?searchtype=author&query=Cluzel%2C+B">Benoit Cluzel</a>, <a href="/search/physics?searchtype=author&query=Grelu%2C+P">Philippe Grelu</a>, <a href="/search/physics?searchtype=author&query=Coillet%2C+A">Aurelien Coillet</a>, <a href="/search/physics?searchtype=author&query=Qiu%2C+F">Feng Qiu</a>, <a href="/search/physics?searchtype=author&query=Ying%2C+L">Lei Ying</a>, <a href="/search/physics?searchtype=author&query=Sha%2C+W">Wei Sha</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+X">Xiaofeng Liu</a>, <a href="/search/physics?searchtype=author&query=Qiu%2C+J">Jianrong Qiu</a>, <a href="/search/physics?searchtype=author&query=Zhao%2C+D">Ding Zhao</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+W">Wei Yan</a>, <a href="/search/physics?searchtype=author&query=Wu%2C+D">Duanduan Wu</a>, <a href="/search/physics?searchtype=author&query=Shen%2C+X">Xiang Shen</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+J">Jiyong Wang</a>, <a href="/search/physics?searchtype=author&query=Qiu%2C+M">Min Qiu</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2201.03855v2-abstract-short" style="display: inline;"> Metafibers expand the functionalities of conventional optical fibers to unprecedented nanoscale light manipulations by integrating metasurfaces on the fiber tips, becoming an emerging light-coupling platform for both nanoscience and fiber optics communities. Mostly exploring the isolated bare fibers, current metafibers remain as proof-of-concept demonstrations due to a lack of standard interfaces… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.03855v2-abstract-full').style.display = 'inline'; document.getElementById('2201.03855v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2201.03855v2-abstract-full" style="display: none;"> Metafibers expand the functionalities of conventional optical fibers to unprecedented nanoscale light manipulations by integrating metasurfaces on the fiber tips, becoming an emerging light-coupling platform for both nanoscience and fiber optics communities. Mostly exploring the isolated bare fibers, current metafibers remain as proof-of-concept demonstrations due to a lack of standard interfaces with the universal fiber networks. Here, we develop new methodologies to fabricate well-defined plasmonic metasurfaces directly on the end facets of commercial single mode fiber jumpers using standard planar technologies and provide a first demonstration of their practical applications in the nonlinear optics regime. Featuring plug-play connections with fiber circuitry and arbitrary metasurfaces landscapes, the metafibers with tunable plasmonic resonances are implemented into fiber laser cavities, yielding all-fiber sub-picosecond (minimum 513 fs) soliton mode locked lasers at optical wavelengths of 1.5 micrometer and 2 micrometer, demonstrating their unusual polarimetric nonlinear transfer functions and superior saturation absorption responses. Novel insights into the physical mechanisms behind the saturable absorption of plasmonic metasurfaces are provided. The nanofabrication process flow is compatible with existing cleanroom technologies, offering metafibers an avenue to be a regular member of functionalized fiber components. The work paves the way towards next generation of ultrafast fiber lasers, optical frequency combs, optical neural networks and ultracompact "all-in-fibers" optical systems for sensing, imaging, communications, and many others. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.03855v2-abstract-full').style.display = 'none'; document.getElementById('2201.03855v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 28 September, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 11 January, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">27 pages, 15 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2112.00521">arXiv:2112.00521</a> <span> [<a href="https://arxiv.org/pdf/2112.00521">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> </div> <p class="title is-5 mathjax"> A scatter correction method for Multi-MeV Flash Radiography </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qinggang Jia</a>, <a href="/search/physics?searchtype=author&query=Mao%2C+P">Peng-Cheng Mao</a>, <a href="/search/physics?searchtype=author&query=Yang-Bo"> Yang-Bo</a>, <a href="/search/physics?searchtype=author&query=Shi%2C+D">Dun-Fu Shi</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+L">Ling-Yu Zhang</a>, <a href="/search/physics?searchtype=author&query=Deng-Li"> Deng-Li</a>, <a href="/search/physics?searchtype=author&query=Xu%2C+H">Hai-Bo Xu</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2112.00521v1-abstract-short" style="display: inline;"> Multi-MeV flash radiography is often used as the primary diagnostic technique for high energy and density (HED) physics experiments. Primary X-ray which is attenuated by the object offers density information of the object. For a thick metal object with area density as high as 150 g/cm2, the rest part of primary X-ray which passes through the object may drowned in scattered X-ray fog. It seriously… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2112.00521v1-abstract-full').style.display = 'inline'; document.getElementById('2112.00521v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2112.00521v1-abstract-full" style="display: none;"> Multi-MeV flash radiography is often used as the primary diagnostic technique for high energy and density (HED) physics experiments. Primary X-ray which is attenuated by the object offers density information of the object. For a thick metal object with area density as high as 150 g/cm2, the rest part of primary X-ray which passes through the object may drowned in scattered X-ray fog. It seriously limits accuracy of density quantification. In this research, an online scatter estimation method is newly designed which can be easily arranged by putting an additional slit collimator downstream of the general X-ray radiography layout. The basic ideal of this method is that the proportion of scatter and primary x-ray will be changed a lot when x-ray passes through a slit like collimation, then scatter component is solvable with known the collimation performance of the silt on scatter and primary x-ray. Monte Carlo simulation shows that, with this method, evaluation error of average scatter is less than 2% when object area density is as high as 200 g/cm2. In addition to the average scatter, an accelerated Monte Carlo method is developed to obtain scatter distribution in iterative reconstruction. By employing the Genetic algorithm as an optimizer, reconstruction can be done by searching a density which projection with scatter best matches experimental result. This reconstruction method requires neither a priori-knowledge such as mass restriction nor regularization. Simulations show that for France Test Object (FTO), the error of reconstructed density is less than 2%, and uncertainty basically covers the real density. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2112.00521v1-abstract-full').style.display = 'none'; document.getElementById('2112.00521v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 December, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2021. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2105.09550">arXiv:2105.09550</a> <span> [<a href="https://arxiv.org/pdf/2105.09550">pdf</a>, <a href="https://arxiv.org/format/2105.09550">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> </div> <p class="title is-5 mathjax"> High duty cycle EUV radiation source based on inverse Compton scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Huang%2C+R">Ruixuan Huang</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2105.09550v1-abstract-short" style="display: inline;"> Inverse Compton scattering (ICS) can obtain quasi-monochromatic and directional EUV radiation via a MeV-scale energy electron beam and a micron-scale wavelength laser beam, which enables a dramatic reduction in dimension and expense of the system, and makes it an attractive technology in research, industry, medicine and homeland security. Here we propose an EUV source based on high repetition ICS… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.09550v1-abstract-full').style.display = 'inline'; document.getElementById('2105.09550v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2105.09550v1-abstract-full" style="display: none;"> Inverse Compton scattering (ICS) can obtain quasi-monochromatic and directional EUV radiation via a MeV-scale energy electron beam and a micron-scale wavelength laser beam, which enables a dramatic reduction in dimension and expense of the system, and makes it an attractive technology in research, industry, medicine and homeland security. Here we propose an EUV source based on high repetition ICS system. The scheme exploits the output from the laser-electron interaction between a MW-ps laser at MHz repetition-rate and a high quality electron beam with an energy of a few MeV at MHz repetition-rate. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.09550v1-abstract-full').style.display = 'none'; document.getElementById('2105.09550v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 20 May, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 2 figures, submited to IPAC 2021</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2104.02956">arXiv:2104.02956</a> <span> [<a href="https://arxiv.org/pdf/2104.02956">pdf</a>, <a href="https://arxiv.org/format/2104.02956">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Computational Physics">physics.comp-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1016/j.ijmecsci.2021.106661">10.1016/j.ijmecsci.2021.106661 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Exploring the design space for nonlinear buckling of composite thin-walled lenticular tubes under pure bending </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qilong Jia</a>, <a href="/search/physics?searchtype=author&query=An%2C+N">Ning An</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+X">Xiaofei Ma</a>, <a href="/search/physics?searchtype=author&query=Zhou%2C+J">Jinxiong Zhou</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2104.02956v2-abstract-short" style="display: inline;"> This paper presents an automatic finite element simulation scheme accounting for high geometric nonlinearity and the difference between linear and nonlinear buckling of composite thin-walled lenticular tubes (CTLTs). Parameterizing of cross-section shapes and generation of design space for CTLTs with both circular and parabolic arcs were accomplished, and several key factors were identified, in pa… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2104.02956v2-abstract-full').style.display = 'inline'; document.getElementById('2104.02956v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2104.02956v2-abstract-full" style="display: none;"> This paper presents an automatic finite element simulation scheme accounting for high geometric nonlinearity and the difference between linear and nonlinear buckling of composite thin-walled lenticular tubes (CTLTs). Parameterizing of cross-section shapes and generation of design space for CTLTs with both circular and parabolic arcs were accomplished, and several key factors were identified, in particular the contrary effect of lumbus length and parabolic coefficient on the bending stiffness anisotropy. The first quantitative comparison of triangular rollable and collapsible (TRAC) booms and CTLTs is given in terms of bending performance in two directions, showing that the optimal CTLT carefully selected from the design space demonstrates a comparable or even better performance than the TRAC boom. This is of great importance from both academic and engineering perspectives. Our efforts enhance the understanding of nonlinear buckling and post-buckling behavior of CTLTs, and provide guidelines for future design of CTLTs with desirable performance. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2104.02956v2-abstract-full').style.display = 'none'; document.getElementById('2104.02956v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 July, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 7 April, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Int. J. Mech. Sci. 207 (2021) 106661 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2102.06297">arXiv:2102.06297</a> <span> [<a href="https://arxiv.org/pdf/2102.06297">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1039/D1TC00682G">10.1039/D1TC00682G <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Large-Size Free-Standing Single-crystal b-Ga2O3 Membranes Fabricated by Hydrogen Implantation and Lift-Off </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zheng%2C+Y">Yixiong Zheng</a>, <a href="/search/physics?searchtype=author&query=Feng%2C+Z">Zixuan Feng</a>, <a href="/search/physics?searchtype=author&query=Bhuiyan%2C+A+F+M+A+U">A F M Anhar Uddin Bhuiyan</a>, <a href="/search/physics?searchtype=author&query=Meng%2C+L">Lingyu Meng</a>, <a href="/search/physics?searchtype=author&query=Dhole%2C+S">Samyak Dhole</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Quanxi Jia</a>, <a href="/search/physics?searchtype=author&query=Zhao%2C+H">Hongping Zhao</a>, <a href="/search/physics?searchtype=author&query=Seo%2C+J">Jung-Hun Seo</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2102.06297v1-abstract-short" style="display: inline;"> In this paper, we have demonstrated the large-size free-standing single-crystal b-Ga2O3 NMs fabricated by the hydrogen implantation and lift-off process directly from MOCVD grown b-Ga2O3 epifilms on native substrates. The optimum implantation conditions were simulated with a Monte-Carlo simulation to obtain the high hydrogen concentration with a narrow ion distribution at the desired depth. Two as… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.06297v1-abstract-full').style.display = 'inline'; document.getElementById('2102.06297v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2102.06297v1-abstract-full" style="display: none;"> In this paper, we have demonstrated the large-size free-standing single-crystal b-Ga2O3 NMs fabricated by the hydrogen implantation and lift-off process directly from MOCVD grown b-Ga2O3 epifilms on native substrates. The optimum implantation conditions were simulated with a Monte-Carlo simulation to obtain the high hydrogen concentration with a narrow ion distribution at the desired depth. Two as grown b-Ga2O3 samples with different orientation ([100] and [001]) were used and successfully create 1.2 um thick b-Ga2O3 NMs without any physical damages. These b-Ga2O3 NMs were then transfer-printed onto rigid and flexible substrates such as SiC substrate and polyimide substrate. Various material characterizations were performed to investigate the crystal quality, surface morphology, optical property, mechanical property, and bandgap before and after the lift-off and revealed that good material quality is maintained. This result offers several benefits in that the thickness, doping, and size of b-Ga2O3 NMs can be fully controlled. Moreover, more advanced b-Ga2O3-based NM structures such as (AlxGa1-x)2O3/Ga2O3 heterostructure NMs can be directly created from their bulk epitaxy substrates thus this result provides a viable route for the realization of high performance b-Ga2O3 NM-based electronics and optoelectronics that can be built on various substrates and platforms. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.06297v1-abstract-full').style.display = 'none'; document.getElementById('2102.06297v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 February, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2021. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2006.00990">arXiv:2006.00990</a> <span> [<a href="https://arxiv.org/pdf/2006.00990">pdf</a>, <a href="https://arxiv.org/format/2006.00990">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Classical Physics">physics.class-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1119/10.0011387">10.1119/10.0011387 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> On the nonlinearity of a tuning fork </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Xiao%2C+L">Lintao Xiao</a>, <a href="/search/physics?searchtype=author&query=Bao%2C+C">Chenyu Bao</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qiuhan Jia</a>, <a href="/search/physics?searchtype=author&query=Wu%2C+H">Haoyang Wu</a>, <a href="/search/physics?searchtype=author&query=Zhou%2C+H">Huijun Zhou</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+S">Sihui Wang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2006.00990v1-abstract-short" style="display: inline;"> Tuning fork experiments at the undergraduate level usually only demonstrate a tuning fork's linear resonance. In this paper, we introduce an experiment that can be used to measure the nonlinear tuning curve of a regular tuning fork. Using double-grating Doppler interferometry, we achieve measurement accuracy within ten microns. With this experiment setup, we observe typical nonlinear behaviors of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.00990v1-abstract-full').style.display = 'inline'; document.getElementById('2006.00990v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2006.00990v1-abstract-full" style="display: none;"> Tuning fork experiments at the undergraduate level usually only demonstrate a tuning fork's linear resonance. In this paper, we introduce an experiment that can be used to measure the nonlinear tuning curve of a regular tuning fork. Using double-grating Doppler interferometry, we achieve measurement accuracy within ten microns. With this experiment setup, we observe typical nonlinear behaviors of the tuning fork such as the softening tuning curve and jump phenomena. Our experiment is inexpensive and easy to operate. It provides an integrated experiment for intermediate-level students and a basis for senior research projects. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.00990v1-abstract-full').style.display = 'none'; document.getElementById('2006.00990v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">11 pages, 5 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2005.04285">arXiv:2005.04285</a> <span> [<a href="https://arxiv.org/pdf/2005.04285">pdf</a>, <a href="https://arxiv.org/format/2005.04285">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OL.397321">10.1364/OL.397321 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Optical phase conjugation in backward Raman amplification </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Qu%2C+K">Kenan Qu</a>, <a href="/search/physics?searchtype=author&query=Fisch%2C+N+J">Nathaniel J. Fisch</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2005.04285v1-abstract-short" style="display: inline;"> Compression of an intense laser pulse using backward Raman amplification (BRA) in plasma, followed by vacuum focusing to a small spot size, can produce unprecedented ultrarelativistic laser intensities. The plasma density inhomogeneity during BRA, however, causes laser phase and amplitude distortions, limiting the pulse focusability. To solve the issue of distortion, we investigate the use of opti… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.04285v1-abstract-full').style.display = 'inline'; document.getElementById('2005.04285v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2005.04285v1-abstract-full" style="display: none;"> Compression of an intense laser pulse using backward Raman amplification (BRA) in plasma, followed by vacuum focusing to a small spot size, can produce unprecedented ultrarelativistic laser intensities. The plasma density inhomogeneity during BRA, however, causes laser phase and amplitude distortions, limiting the pulse focusability. To solve the issue of distortion, we investigate the use of optical phase conjugation as the seed pulse for BRA. We show that the phase conjugated laser pulses can retain focusability in the nonlinear pump-depletion regime of BRA, but not so easily in the linear amplification regime. This somewhat counter-intuitive result is because the nonlinear pump-depletion regime features a shorter amplification distance, and hence less phase distortion due to wave-wave interaction, than the linear amplification regime. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.04285v1-abstract-full').style.display = 'none'; document.getElementById('2005.04285v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 8 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2020. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2004.05556">arXiv:2004.05556</a> <span> [<a href="https://arxiv.org/pdf/2004.05556">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> </div> <p class="title is-5 mathjax"> Smith-Purcell radiation from a charge moving above a finite-length grating with rectangular profiles </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Li%2C+W">Weiwei Li</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+W">Weihao Liu</a>, <a href="/search/physics?searchtype=author&query=He%2C+Z">Zhigang He</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+L">Lin Wang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.05556v1-abstract-short" style="display: inline;"> Smith-Purcell radiation is generated by a charged particle beam passing close to the surface of a diffraction grating which has a strong dependency of the emitted radiation intensity on the form of the grating profile. For relativistic electron beam, it is important to take into account the number of grating periods in practical SPR setups. In this paper, the theoretical investigations of Smith-Pu… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.05556v1-abstract-full').style.display = 'inline'; document.getElementById('2004.05556v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.05556v1-abstract-full" style="display: none;"> Smith-Purcell radiation is generated by a charged particle beam passing close to the surface of a diffraction grating which has a strong dependency of the emitted radiation intensity on the form of the grating profile. For relativistic electron beam, it is important to take into account the number of grating periods in practical SPR setups. In this paper, the theoretical investigations of Smith-Purcell radiation from a three-dimensional bunch of relativistic electrons that moves at constant speed parallel to an electrically perfectly conducting grating with finite rectangular grooves are carried out by using the modal matching method. This model may offer a new efficient tool for terahertz production by SPR interaction and for nondestructive bunch-length measurements by SPR. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.05556v1-abstract-full').style.display = 'none'; document.getElementById('2004.05556v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1910.06555">arXiv:1910.06555</a> <span> [<a href="https://arxiv.org/pdf/1910.06555">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1016/j.actamat.2019.10.020">10.1016/j.actamat.2019.10.020 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Integration of the Noncollinear Antiferromagnetic Metal Mn3Sn onto Ferroelectric Oxides for Electric-Field Control </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Wang%2C+X">Xiaoning Wang</a>, <a href="/search/physics?searchtype=author&query=Feng%2C+Z">Zexin Feng</a>, <a href="/search/physics?searchtype=author&query=Qin%2C+P">Peixin Qin</a>, <a href="/search/physics?searchtype=author&query=Yan%2C+H">Han Yan</a>, <a href="/search/physics?searchtype=author&query=Zhou%2C+X">Xiaorong Zhou</a>, <a href="/search/physics?searchtype=author&query=Guo%2C+H">Huixin Guo</a>, <a href="/search/physics?searchtype=author&query=Leng%2C+Z">Zhaoguogang Leng</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+W">Weiqi Chen</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qiannan Jia</a>, <a href="/search/physics?searchtype=author&query=Hu%2C+Z">Zexiang Hu</a>, <a href="/search/physics?searchtype=author&query=Wu%2C+H">Haojiang Wu</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+X">Xin Zhang</a>, <a href="/search/physics?searchtype=author&query=Jiang%2C+C">Chengbao Jiang</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+Z">Zhiqi Liu</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1910.06555v1-abstract-short" style="display: inline;"> Non-collinear antiferromagnetic materials have received dramatically increasing attention in the field of spintronics as their exotic topological features such as the Berry-curvature-induced anomalous Hall effect and possible magnetic Weyl states could be utilized in future topological antiferromagnetic spintronic devices. In this work, we report the successful integration of the antiferromagnetic… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.06555v1-abstract-full').style.display = 'inline'; document.getElementById('1910.06555v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1910.06555v1-abstract-full" style="display: none;"> Non-collinear antiferromagnetic materials have received dramatically increasing attention in the field of spintronics as their exotic topological features such as the Berry-curvature-induced anomalous Hall effect and possible magnetic Weyl states could be utilized in future topological antiferromagnetic spintronic devices. In this work, we report the successful integration of the antiferromagnetic metal Mn3Sn thin films onto ferroelectric oxide PMN-PT. By optimizing growth, we realized the large anomalous Hall effect with small switching magnetic fields of several tens mT fully comparable to those of bulk Mn3Sn single crystals, anisotropic magnetoresistance and negative parallel magnetoresistance in Mn3Sn thin films with antiferromagnetic order, which are similar to the signatures of the Weyl state in bulk Mn3Sn single crystals. More importantly, we found that the anomalous Hall effect in antiferromagnetic Mn3Sn thin films can be manipulated by electric fields applied onto the ferroelectric materials, thus demonstrating the feasibility of Mn3Sn-based topological spintronic devices operated in an ultralow power manner. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.06555v1-abstract-full').style.display = 'none'; document.getElementById('1910.06555v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 15 October, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">25 pages, 10 figure. Accepted in Acta Materialia</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Acta Materialia 181, 537 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1905.12036">arXiv:1905.12036</a> <span> [<a href="https://arxiv.org/pdf/1905.12036">pdf</a>, <a href="https://arxiv.org/format/1905.12036">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Fluid Dynamics">physics.flu-dyn</span> </div> </div> <p class="title is-5 mathjax"> Explorative gradient method for active drag reduction of the fluidic pinball and slanted Ahmed body </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Li%2C+Y">Yiqing Li</a>, <a href="/search/physics?searchtype=author&query=Cui%2C+W">Wenshi Cui</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Li%2C+Q">Qiliang Li</a>, <a href="/search/physics?searchtype=author&query=Yang%2C+Z">Zhigang Yang</a>, <a href="/search/physics?searchtype=author&query=Morzy%C5%84ski%2C+M">Marek Morzy艅ski</a>, <a href="/search/physics?searchtype=author&query=Noack%2C+B+R">Bernd R. Noack</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1905.12036v2-abstract-short" style="display: inline;"> We address a challenge of active flow control: the optimization of many actuation parameters guaranteeing fast convergence and avoiding suboptimal local minima. This challenge is addressed by a new optimizer, called explorative gradient method (EGM). EGM alternatively performs one exploitive downhill simplex step and an explorative Latin hypercube sampling iteration. Thus, the convergence rate of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1905.12036v2-abstract-full').style.display = 'inline'; document.getElementById('1905.12036v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1905.12036v2-abstract-full" style="display: none;"> We address a challenge of active flow control: the optimization of many actuation parameters guaranteeing fast convergence and avoiding suboptimal local minima. This challenge is addressed by a new optimizer, called explorative gradient method (EGM). EGM alternatively performs one exploitive downhill simplex step and an explorative Latin hypercube sampling iteration. Thus, the convergence rate of a gradient based method is guaranteed while, at the same time, better minima are explored. For an analytical multi-modal test function, EGM is shown to significantly outperform the downhill simplex method, the random restart variant, Latin hypercube sampling, Monte Carlo iterations and the genetic algorithm. EGM is applied to minimize the net drag power of the two-dimensional fluidic pinball benchmark with three cylinder rotations as actuation parameters. The net drag power is reduced by $40\%$ employing direct numerical simulations at a Reynolds number of $100$ based on the cylinder diameter. This optimal actuation leads to $98\%$ drag reduction employing Coanda forcing for boat tailing and partial stabilization of vortex shedding. The price is an actuation energy corresponding to $58\%$ of the unforced parasitic drag power. EGM is also used to minimize drag of the $35^\circ$ slanted Ahmed body employing distributed steady blowing with 10 inputs. $17\%$ drag reduction are achieved using Reynolds-Averaged Navier-Stokes simulations (RANS) at the Reynolds number $Re_H=1.9 \times 10^5$ based on the height of the Ahmed body. The optimal actuation emulates boat tailing by inward-directed blowing with velocities which are comparable to the oncoming velocity. We expect that EGM will be employed as efficient optimizer in many future active flow control plants. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1905.12036v2-abstract-full').style.display = 'none'; document.getElementById('1905.12036v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 30 October, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 28 May, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2019. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1807.03438">arXiv:1807.03438</a> <span> [<a href="https://arxiv.org/pdf/1807.03438">pdf</a>, <a href="https://arxiv.org/format/1807.03438">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevApplied.12.044040">10.1103/PhysRevApplied.12.044040 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Enhancing intrinsic detection efficiency of superconducting nanowire single-photon detectors via helium ion irradiation </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhang%2C+W">Weijun Zhang</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi Jia</a>, <a href="/search/physics?searchtype=author&query=You%2C+L">Lixing You</a>, <a href="/search/physics?searchtype=author&query=Ou%2C+X">Xin Ou</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">Hao Li</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+L">Lu Zhang</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+Z">Zhen Wang</a>, <a href="/search/physics?searchtype=author&query=Xie%2C+X">Xiaoming Xie</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1807.03438v1-abstract-short" style="display: inline;"> Realizing an NbN superconducting nanowire single-photon detector (SNSPD) with a 100% intrinsic detection efficiency (IDE) at the near-infrared wavelengths is still challenging. Herein, we developed a post-processing method to increase the IDE of NbN SNSPDs to near unity using a 20 keV helium ion irradiation. The IDE enhancement was achieved owing to the ion-induced reduction of the superconducting… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1807.03438v1-abstract-full').style.display = 'inline'; document.getElementById('1807.03438v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1807.03438v1-abstract-full" style="display: none;"> Realizing an NbN superconducting nanowire single-photon detector (SNSPD) with a 100% intrinsic detection efficiency (IDE) at the near-infrared wavelengths is still challenging. Herein, we developed a post-processing method to increase the IDE of NbN SNSPDs to near unity using a 20 keV helium ion irradiation. The IDE enhancement was achieved owing to the ion-induced reduction of the superconducting energy gap and the electron density of states at the Fermi level, determined with the electrical and magnetic transport measurements. The change in optical absorptance of the irradiated SNSPD was negligible as confirmed by the measured optical reflectance and system detection efficiency (SDE). Benefited with the IDE enhancement, the SDE of an irradiated device was significantly increased from 49% to 92% at 2.2 K for a 1550 nm wavelength. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1807.03438v1-abstract-full').style.display = 'none'; document.getElementById('1807.03438v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 July, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 2 figures, 2 tables</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review Applied 12, 044040 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1806.00162">arXiv:1806.00162</a> <span> [<a href="https://arxiv.org/pdf/1806.00162">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1748-0221/15/03/P03008">10.1088/1748-0221/15/03/P03008 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Numerical Method for Free Electron Laser using an Overmoded Rectangular Waveguide </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Li%2C+W">Weiwei Li</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">Heting Li</a>, <a href="/search/physics?searchtype=author&query=He%2C+Z">Zhigang He</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+L">Lin Wang</a>, <a href="/search/physics?searchtype=author&query=Lu%2C+Y">Yalin Lu</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1806.00162v1-abstract-short" style="display: inline;"> Numerical simulation codes are basic tools for designing Free Electron Lasers (FELs). This paper describes a numerical method for the time-dependent, three-dimensional simulation of the free electron laser (FEL) using a rectangular waveguide within overmoded configuration when the radiation wavelength is much shorter than the waveguide cut-off wavelength. Instead of developing a new code, the GENE… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.00162v1-abstract-full').style.display = 'inline'; document.getElementById('1806.00162v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1806.00162v1-abstract-full" style="display: none;"> Numerical simulation codes are basic tools for designing Free Electron Lasers (FELs). This paper describes a numerical method for the time-dependent, three-dimensional simulation of the free electron laser (FEL) using a rectangular waveguide within overmoded configuration when the radiation wavelength is much shorter than the waveguide cut-off wavelength. Instead of developing a new code, the GENESIS simulation code is modified for our purpose. This method presented here can be used for extending the capacity of GENESIS to cover this special configuration. The major modification is to apply the metal boundary conditions on the field equations in a limited rectangular region and the full Cartesian mesh using the Alternating Direction Implicit (ADI) integration scheme to solve the field equation remains adopted. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.00162v1-abstract-full').style.display = 'none'; document.getElementById('1806.00162v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 31 May, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2018. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1804.07358">arXiv:1804.07358</a> <span> [<a href="https://arxiv.org/pdf/1804.07358">pdf</a>, <a href="https://arxiv.org/ps/1804.07358">ps</a>, <a href="https://arxiv.org/format/1804.07358">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevE.98.023202">10.1103/PhysRevE.98.023202 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Theory of electromagnetic wave frequency upconversion in dynamic media </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Qu%2C+K">Kenan Qu</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Edwards%2C+M+R">Matthew R. Edwards</a>, <a href="/search/physics?searchtype=author&query=Fisch%2C+N+J">Nathaniel J. Fisch</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1804.07358v2-abstract-short" style="display: inline;"> Frequency upconversion of an electromagnetic wave can occur in ionized plasma with decreasing electric permittivity and in split-ring resonator-structure metamaterials with decreasing magnetic permeability. We develop a general theory to describe the evolution of the wave frequency, amplitude, and energy density in homogeneous media with a temporally decreasing refractive index. We find that upcon… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.07358v2-abstract-full').style.display = 'inline'; document.getElementById('1804.07358v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1804.07358v2-abstract-full" style="display: none;"> Frequency upconversion of an electromagnetic wave can occur in ionized plasma with decreasing electric permittivity and in split-ring resonator-structure metamaterials with decreasing magnetic permeability. We develop a general theory to describe the evolution of the wave frequency, amplitude, and energy density in homogeneous media with a temporally decreasing refractive index. We find that upconversion of the wave frequency is necessarily accompanied by partitioning of the wave energy into low-frequency modes, which sets an upper limit on the energy conversion efficiency. The efficiency limits are obtained for both varying permittivity and varying permeability. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.07358v2-abstract-full').style.display = 'none'; document.getElementById('1804.07358v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 19 April, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 2 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. E 98, 023202 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1710.07801">arXiv:1710.07801</a> <span> [<a href="https://arxiv.org/pdf/1710.07801">pdf</a>, <a href="https://arxiv.org/ps/1710.07801">ps</a>, <a href="https://arxiv.org/format/1710.07801">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevAccelBeams.21.020701">10.1103/PhysRevAccelBeams.21.020701 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Generation of coherent two-color pulses at the two adjacent harmonics in a seeded free-electron laser </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhao%2C+Z">Zhouyu Zhao</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">Heting Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1710.07801v1-abstract-short" style="display: inline;"> The growing requirements of pump-probe techniques and nonlinear optics experiments greatly promote the studies of two-color free-electron lasers (FELs). We propose a new method to generate coherent two-color pulses in a high-gain harmonic generation (HGHG) FEL. In this scheme, an initial tilted electron beam is sent though the modulator and dispersive section of an HGHG FEL to generate the bunchin… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.07801v1-abstract-full').style.display = 'inline'; document.getElementById('1710.07801v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1710.07801v1-abstract-full" style="display: none;"> The growing requirements of pump-probe techniques and nonlinear optics experiments greatly promote the studies of two-color free-electron lasers (FELs). We propose a new method to generate coherent two-color pulses in a high-gain harmonic generation (HGHG) FEL. In this scheme, an initial tilted electron beam is sent though the modulator and dispersive section of an HGHG FEL to generate the bunching at harmonics of the seed laser. Then a transverse gradient undulator (TGU) is adopted as the radiator and in such radiator, only two separated fractions of the tilted beam will resonate at two adjacent harmonics of the seed laser and are enabled to emit the coherent two-color pulses simultaneously. The time separation between the two pulses are on the order of hundreds of femtoseconds, and can be precisely controlled by varying the tilted amplitude of the electron beam and/or the transverse gradient of the TGU radiator. Numerical simulations confirm the validity and feasibility of this scheme in the EUV waveband. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.07801v1-abstract-full').style.display = 'none'; document.getElementById('1710.07801v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 21 October, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Accel. Beams 21, 020701 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1709.07780">arXiv:1709.07780</a> <span> [<a href="https://arxiv.org/pdf/1709.07780">pdf</a>, <a href="https://arxiv.org/format/1709.07780">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevE.96.053207">10.1103/PhysRevE.96.053207 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Plasma q-plate for generation and manipulation of intense optical vortices </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Qu%2C+K">Kenan Qu</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Fisch%2C+N+J">Nathaniel J. Fisch</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1709.07780v2-abstract-short" style="display: inline;"> An optical vortex is a light wave with a twisting wavefront around its propagation axis and null intensity in the beam center. Its unique spatial structure of field lends itself to a broad range of applications, including optical communication, quantum information, superresolution microscopy, and multi-dimensional manipulation of particles. However, accessible intensity of optical vortices have be… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1709.07780v2-abstract-full').style.display = 'inline'; document.getElementById('1709.07780v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1709.07780v2-abstract-full" style="display: none;"> An optical vortex is a light wave with a twisting wavefront around its propagation axis and null intensity in the beam center. Its unique spatial structure of field lends itself to a broad range of applications, including optical communication, quantum information, superresolution microscopy, and multi-dimensional manipulation of particles. However, accessible intensity of optical vortices have been limited to material ionization threshold. This limitation might be removed by using the plasma medium. Here we propose the design of suitably magnetized plasmas which, functioning as a q-plate, leads to a direct convertion from a high-intensity Gaussian beam into a twisted beam. A circularly polarized laser beam in the plasma accumulates an azimuthal-angle-dependent phase shift and hence forms a twisting wavefront. Our three-dimensional particle-in-cell simulations demonstrate extremely high power conversion efficiency. The plasma q-plate can work in a large range of frequencies spanning from terahertz to the optical domain. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1709.07780v2-abstract-full').style.display = 'none'; document.getElementById('1709.07780v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 30 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 22 September, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. E 96, 053207 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1704.01694">arXiv:1704.01694</a> <span> [<a href="https://arxiv.org/pdf/1704.01694">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Atomic and Molecular Clusters">physics.atm-clus</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1063/1.4980062">10.1063/1.4980062 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Photoinduced coherent acoustic phonon dynamics inside Mott insulator Sr2IrO4 films observed by femtosecond X-ray pulses </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhang%2C+B">Bing-Bing Zhang</a>, <a href="/search/physics?searchtype=author&query=Liu%2C+J">Jian Liu</a>, <a href="/search/physics?searchtype=author&query=Wei%2C+X">Xu Wei</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+D">Da-Rui Sun</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Quan-Jie Jia</a>, <a href="/search/physics?searchtype=author&query=Li%2C+Y">Yuelin Li</a>, <a href="/search/physics?searchtype=author&query=Tao%2C+Y">Ye Tao</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1704.01694v1-abstract-short" style="display: inline;"> We investigate the transient photoexcited lattice dynamics in a layered perovskite Mott insulator Sr2IrO4 by femtosecond X-ray diffraction using a laser plasma-based X-ray source. Ultrafast structural dynamics of Sr2IrO4 thin films are determined by observing the shift and broadening of the (0012) Bragg diffraction after excitation by 1.5 eV and 3.0 eV pump photons for films with different thickne… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1704.01694v1-abstract-full').style.display = 'inline'; document.getElementById('1704.01694v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1704.01694v1-abstract-full" style="display: none;"> We investigate the transient photoexcited lattice dynamics in a layered perovskite Mott insulator Sr2IrO4 by femtosecond X-ray diffraction using a laser plasma-based X-ray source. Ultrafast structural dynamics of Sr2IrO4 thin films are determined by observing the shift and broadening of the (0012) Bragg diffraction after excitation by 1.5 eV and 3.0 eV pump photons for films with different thicknesses. The observed transient lattice response can be well interpreted as a distinct three-step dynamics due to the propagation of coherent acoustic phonons generated by the photoinduced quasiparticles (QP). Employing a normalized phonon propagation model, we found that the photoinduced angular shifts of the Bragg peak collapse into a universal curve after introducing a normalized coordinates to account for different thicknesses and pump photon energies, pinpointing the origin of the lattice distortion and its early evolution. In addition, a transient photocurrent measurement indicates that the photoinduced QPs are charge neutral excitons. Mapping the phonon propagation and correlating its dynamics with the QP by ultrafast X-ray diffraction (UXRD) establish a powerful way to study electron-phonon coupling and uncover the exotic physics in strongly correlated systems under nonequilibrium conditions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1704.01694v1-abstract-full').style.display = 'none'; document.getElementById('1704.01694v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 April, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">11 pages,4 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1704.01369">arXiv:1704.01369</a> <span> [<a href="https://arxiv.org/pdf/1704.01369">pdf</a>, <a href="https://arxiv.org/ps/1704.01369">ps</a>, <a href="https://arxiv.org/format/1704.01369">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Biological Physics">physics.bio-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Biomolecules">q-bio.BM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.119.138102">10.1103/PhysRevLett.119.138102 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Angstrom-resolution single-molecule fluorescence resonance energy transfer reveals mechanisms of DNA helicases </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Lin%2C+W">Wenxia Lin</a>, <a href="/search/physics?searchtype=author&query=Ma%2C+J">Jianbing Ma</a>, <a href="/search/physics?searchtype=author&query=Nong%2C+D">Daguan Nong</a>, <a href="/search/physics?searchtype=author&query=Xu%2C+C">Chunhua Xu</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+B">Bo Zhang</a>, <a href="/search/physics?searchtype=author&query=Li%2C+J">Jinghua Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi Jia</a>, <a href="/search/physics?searchtype=author&query=Dou%2C+S">Shuoxing Dou</a>, <a href="/search/physics?searchtype=author&query=Xi%2C+X">Xuguang Xi</a>, <a href="/search/physics?searchtype=author&query=Lu%2C+Y">Ying Lu</a>, <a href="/search/physics?searchtype=author&query=Li%2C+M">Ming Li</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1704.01369v1-abstract-short" style="display: inline;"> Single-molecule FRET is widely used to study helicases by detecting distance changes between a fluorescent donor and an acceptor anchored to overhangs of a forked DNA duplex. However, it has lacked single-base pair (1-bp) resolution required for revealing stepping dynamics in unwinding because FRET signals are usually blurred by thermal fluctuations of the overhangs. We designed a nanotensioner in… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1704.01369v1-abstract-full').style.display = 'inline'; document.getElementById('1704.01369v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1704.01369v1-abstract-full" style="display: none;"> Single-molecule FRET is widely used to study helicases by detecting distance changes between a fluorescent donor and an acceptor anchored to overhangs of a forked DNA duplex. However, it has lacked single-base pair (1-bp) resolution required for revealing stepping dynamics in unwinding because FRET signals are usually blurred by thermal fluctuations of the overhangs. We designed a nanotensioner in which a short DNA is bent to exert a force on the overhangs, just as in optical/magnetic tweezers. The strategy improved the resolution of FRET to 0.5 bp, high enough to uncover the differences in DNA unwinding by yeast Pif1 and E. coli RecQ whose unwinding behaviors cannot be differentiated by currently practiced methods. We found that Pif1 exhibits 1-bp-stepping kinetics, while RecQ breaks 1 bp at a time but questers the nascent nucleotides and releases them randomly. The high-resolution data allowed us to propose a three-parameter model to quantitatively interpret the apparently different unwinding behaviors of the two helicases which belong to two superfamilies. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1704.01369v1-abstract-full').style.display = 'none'; document.getElementById('1704.01369v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 April, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 119, 138102 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1704.01289">arXiv:1704.01289</a> <span> [<a href="https://arxiv.org/pdf/1704.01289">pdf</a>, <a href="https://arxiv.org/ps/1704.01289">ps</a>, <a href="https://arxiv.org/format/1704.01289">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/41/10/108101">10.1088/1674-1137/41/10/108101 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The effect of cavity length detuning on the output characteristics for the middle infrared FEL oscillator of FELiChEM </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhao%2C+Z">Zhou-Yu Zhao</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">He-Ting Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi-Ka Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1704.01289v2-abstract-short" style="display: inline;"> FELiChEM is an infrared free electron laser (FEL) facility under construction, which consists of two oscillators generating middle-infrared and far-infrared laser covering the spectral range of 2.5-200 ${\rm{渭m}}$. In this paper, we numerically study the output characteristics of the middle-infrared oscillator with the accurate cavity length detuning. Emphasis is put on the temporal structure of t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1704.01289v2-abstract-full').style.display = 'inline'; document.getElementById('1704.01289v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1704.01289v2-abstract-full" style="display: none;"> FELiChEM is an infrared free electron laser (FEL) facility under construction, which consists of two oscillators generating middle-infrared and far-infrared laser covering the spectral range of 2.5-200 ${\rm{渭m}}$. In this paper, we numerically study the output characteristics of the middle-infrared oscillator with the accurate cavity length detuning. Emphasis is put on the temporal structure of the micropulse and the corresponding spectral bandwidth. Taking the radiation wavelengths of 50 ${\rm{渭m}}$ and 5 ${\rm{渭m}}$ as examples, we show that the output pulse duration can be tuned in the range of 1-6 ps with corresponding bandwidth of 13-0.2\% by adjusting the cavity length detuning. In addition, a special discussion on the comb structure is presented, and it is indicated that the comb structure may arise in the output optical pulse when the normalized slippage length is much smaller than unity. This work has reference value for the operation of FELiChEM and other FEL oscillators. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1704.01289v2-abstract-full').style.display = 'none'; document.getElementById('1704.01289v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 5 April, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2017. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1609.01012">arXiv:1609.01012</a> <span> [<a href="https://arxiv.org/pdf/1609.01012">pdf</a>, <a href="https://arxiv.org/ps/1609.01012">ps</a>, <a href="https://arxiv.org/format/1609.01012">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/41/1/018102">10.1088/1674-1137/41/1/018102 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Design of FELiChEM, the first infrared free-electron laser user facility in China </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Li%2C+H">He-Ting Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi-Ka Jia</a>, <a href="/search/physics?searchtype=author&query=Zhang%2C+S">Shan-Cai Zhang</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+L">Lin Wang</a>, <a href="/search/physics?searchtype=author&query=Yang%2C+Y">Yong-Liang Yang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1609.01012v1-abstract-short" style="display: inline;"> FELiChEM is a new experimental facility under construction at University of Science and Technology of China (USTC), whose core device is two free electron laser oscillators generating middle-infrared and far-infrared laser and covering the spectral range of 2.5-200 $渭$m. It will be a dedicated infrared light source aiming at energy chemistry research. We present the brief design of FEL oscillators… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1609.01012v1-abstract-full').style.display = 'inline'; document.getElementById('1609.01012v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1609.01012v1-abstract-full" style="display: none;"> FELiChEM is a new experimental facility under construction at University of Science and Technology of China (USTC), whose core device is two free electron laser oscillators generating middle-infrared and far-infrared laser and covering the spectral range of 2.5-200 $渭$m. It will be a dedicated infrared light source aiming at energy chemistry research. We present the brief design of FEL oscillators with the emphasis put on the middle-infrared oscillator. Most of the basic parameters are determined and the anticipated performance of the output radiation is given. The first light of FELiChEM is targeted for the end of 2017. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1609.01012v1-abstract-full').style.display = 'none'; document.getElementById('1609.01012v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 4 September, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 8 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Chinese Physics C Vol. 41, No. 1 (2017) 018102 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1607.01488">arXiv:1607.01488</a> <span> [<a href="https://arxiv.org/pdf/1607.01488">pdf</a>, <a href="https://arxiv.org/ps/1607.01488">ps</a>, <a href="https://arxiv.org/format/1607.01488">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/40/11/117004">10.1088/1674-1137/40/11/117004 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Simulation Study on the Emittance Compensation of Off-axis Emitted Beam in RF Photoinjector </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Huang%2C+R">Rui-Xuan Huang</a>, <a href="/search/physics?searchtype=author&query=Mitchell%2C+C">Chad Mitchell</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi-Ka Jia</a>, <a href="/search/physics?searchtype=author&query=Papadopoulos%2C+C">Christos Papadopoulos</a>, <a href="/search/physics?searchtype=author&query=Sannibale%2C+F">Fernando Sannibale</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1607.01488v1-abstract-short" style="display: inline;"> To make full use of photocathode material and improve its quantum efficiency lifetime, it can be necessary to operate laser away from the cathode center in photoinjectors. In RF guns, the off-axis emitted beam will see a time-dependent RF effect, which would generate a significant growth in transverse emittance. It has been demonstrated that such an emittance growth can be almost completely compen… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1607.01488v1-abstract-full').style.display = 'inline'; document.getElementById('1607.01488v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1607.01488v1-abstract-full" style="display: none;"> To make full use of photocathode material and improve its quantum efficiency lifetime, it can be necessary to operate laser away from the cathode center in photoinjectors. In RF guns, the off-axis emitted beam will see a time-dependent RF effect, which would generate a significant growth in transverse emittance. It has been demonstrated that such an emittance growth can be almost completely compensated by orienting the beam on a proper orbit in the downstream RF cavities along the injector. In this paper we analyze in detail the simulation techniques used in reference[1] and the issues associated with them. The optimization of photoinjector systems involving off-axis beams is a challenging problem. To solve this problem, one needs advanced simulation tools including both genetic algorithms and an efficient algorithm for 3D space charge. In this paper, we report on simulation studies where the two codes ASTRA and IMPACT-T are used jointly to overcome these challenges, in order to optimize a system designed to compensate for the emittance growth in a beam emitted off axis. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1607.01488v1-abstract-full').style.display = 'none'; document.getElementById('1607.01488v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 July, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 6 figures, 1 table, it is to be published in Chinese Physics C</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1607.00332">arXiv:1607.00332</a> <span> [<a href="https://arxiv.org/pdf/1607.00332">pdf</a>, <a href="https://arxiv.org/format/1607.00332">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1063/1.4961429">10.1063/1.4961429 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Short-Pulse Amplification by Strongly-Coupled Stimulated Brillouin Scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Edwards%2C+M+R">Matthew R. Edwards</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qing Jia</a>, <a href="/search/physics?searchtype=author&query=Mikhailova%2C+J+M">Julia M. Mikhailova</a>, <a href="/search/physics?searchtype=author&query=Fisch%2C+N+J">Nathaniel J. Fisch</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1607.00332v3-abstract-short" style="display: inline;"> We examine the feasibility of strongly-coupled stimulated Brillouin scattering as a mechanism for the plasma-based amplification of sub-picosecond pulses. In particular, we use fluid theory and particle-in-cell simulations to compare the relative advantages of Raman and Brillouin amplification over a broad range of achievable parameters. </span> <span class="abstract-full has-text-grey-dark mathjax" id="1607.00332v3-abstract-full" style="display: none;"> We examine the feasibility of strongly-coupled stimulated Brillouin scattering as a mechanism for the plasma-based amplification of sub-picosecond pulses. In particular, we use fluid theory and particle-in-cell simulations to compare the relative advantages of Raman and Brillouin amplification over a broad range of achievable parameters. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1607.00332v3-abstract-full').style.display = 'none'; document.getElementById('1607.00332v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 September, 2016; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 1 July, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">16 pages, 11 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Plasmas 23, 083122 (2016) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1511.00625">arXiv:1511.00625</a> <span> [<a href="https://arxiv.org/pdf/1511.00625">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/40/5/057002">10.1088/1674-1137/40/5/057002 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Improved step-by-step chromaticity compensation method for chromatic sextupole optimization </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Liu%2C+G">Gang-Wen Liu</a>, <a href="/search/physics?searchtype=author&query=Bai%2C+Z">Zheng-He Bai</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi-Ka Jia</a>, <a href="/search/physics?searchtype=author&query=Li%2C+W">Wei-Min Li</a>, <a href="/search/physics?searchtype=author&query=Wang%2C+L">Lin Wang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1511.00625v1-abstract-short" style="display: inline;"> The step-by-step chromaticity compensation method for chromatic sextupole optimization and dynamic aperture increase was proposed by E. Levichev and P. Piminov (E. Levichev and P. Piminov, 2006 [1]). Although this method can be used to enlarge the dynamic aperture of storage ring, it has some drawbacks. In this paper, we combined this method with evolutionary computation algorithms, and proposed a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1511.00625v1-abstract-full').style.display = 'inline'; document.getElementById('1511.00625v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1511.00625v1-abstract-full" style="display: none;"> The step-by-step chromaticity compensation method for chromatic sextupole optimization and dynamic aperture increase was proposed by E. Levichev and P. Piminov (E. Levichev and P. Piminov, 2006 [1]). Although this method can be used to enlarge the dynamic aperture of storage ring, it has some drawbacks. In this paper, we combined this method with evolutionary computation algorithms, and proposed an improved version of this method. In the improved method, the drawbacks are avoided, and thus better optimization results can be obtained. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1511.00625v1-abstract-full').style.display = 'none'; document.getElementById('1511.00625v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 2 November, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">10 pages, 10 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1407.7298">arXiv:1407.7298</a> <span> [<a href="https://arxiv.org/pdf/1407.7298">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Plasma Physics">physics.plasm-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/39/12/127005">10.1088/1674-1137/39/12/127005 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Investigating of electrons bunching in a Penning trap and accelerating process for CO2 gas mixture active medium </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Tian%2C+X">Xiu-fang Tian</a>, <a href="/search/physics?searchtype=author&query=Wu%2C+C">Cong-feng Wu</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1407.7298v1-abstract-short" style="display: inline;"> In the presence of an active medium incorporated in a Penning trap, the moving electrons can become bunched, as they get enough energy, they escape the trap forming an optical injector. These bunched electrons can enter next PASER section filled with the same active medium to be accelerated. In this paper, electron dynamics in the presence of gas mixture active medium incorporated in a penning tra… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1407.7298v1-abstract-full').style.display = 'inline'; document.getElementById('1407.7298v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1407.7298v1-abstract-full" style="display: none;"> In the presence of an active medium incorporated in a Penning trap, the moving electrons can become bunched, as they get enough energy, they escape the trap forming an optical injector. These bunched electrons can enter next PASER section filled with the same active medium to be accelerated. In this paper, electron dynamics in the presence of gas mixture active medium incorporated in a penning trap is analyzed by developing an idealized 1D model. We further evaluate the energy exchange occurring as the train of electrons traversing the next PASER section. The results show that the oscillating electrons can be bunched at the resonant frequency of the active medium. The influence of the trapped time and the population inversion are analyzed, which shows that the longer the electrons are trapped, the more energy from the medium the accelerated electrons get, and with the increase of the population inversion, the decelerated electrons virtually unchanged but the accelerated electrons more than double their peak energy values. What is more, the simulation results show that the gas active medium need lower population inversion to bunch the electrons compared to the solid active medium. So the experimental condition is easy to be achieved. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1407.7298v1-abstract-full').style.display = 'none'; document.getElementById('1407.7298v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 July, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2014. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1406.6460">arXiv:1406.6460</a> <span> [<a href="https://arxiv.org/pdf/1406.6460">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/39/4/048101">10.1088/1674-1137/39/4/048101 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Analytical formula of Free Electron Laser exponential gain for non-resonant electron beam </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1406.6460v1-abstract-short" style="display: inline;"> The FEL gain formulas for non-resonant case are studied. For the mono-energetic and non-resonant electron beam, the exact expression of the solution of the FEL characteristic cubic equation is obtained with a form much more simple than that in the literatures, and the gain length as the function of the detuning parameter is explicitly given, then the gain for different detuning parameter and from… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1406.6460v1-abstract-full').style.display = 'inline'; document.getElementById('1406.6460v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1406.6460v1-abstract-full" style="display: none;"> The FEL gain formulas for non-resonant case are studied. For the mono-energetic and non-resonant electron beam, the exact expression of the solution of the FEL characteristic cubic equation is obtained with a form much more simple than that in the literatures, and the gain length as the function of the detuning parameter is explicitly given, then the gain for different detuning parameter and from low to high can be easily calculated. A simplified approximation formula is also given for the exponential gain calculation in the non-resonant case. For the case of the electron beam with an energy spread, the solution of the characteristic cubic equation is given explicitly for rectangular energy distribution and Lorentz distribution, respectively. Moreover the explicit expression also can be used for the solution of the characteristic cubic equation including the impact of the space charge. The transition from the low gain to the high gain is analyzed. The variations of the gain bandwidth and of the detuning parameter for the maximum gain are demonstrated. The applicable ranges of the small signal gain formula and the exponential gain formula are analyzed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1406.6460v1-abstract-full').style.display = 'none'; document.getElementById('1406.6460v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 June, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">9 pages, 8 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1403.2504">arXiv:1403.2504</a> <span> [<a href="https://arxiv.org/pdf/1403.2504">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Nuclear Experiment">nucl-ex</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/38/7/077002">10.1088/1674-1137/38/7/077002 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Development of a Quasi-Periodic Undulator for the HLS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Yang%2C+Y">Yufeng Yang</a>, <a href="/search/physics?searchtype=author&query=Lu%2C+H">Huihua Lu</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+W">Wan Chen</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+S">Shuchen Sun</a>, <a href="/search/physics?searchtype=author&query=Li%2C+Z">Zhiqiang Li</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1403.2504v1-abstract-short" style="display: inline;"> China's first quasi-periodic undulator (QPU) has been developed for the Hefei Light Source (HLS). It uses a magnetic configuration with varied thicknesses of NdFeB blocks, based on the QPU of European Synchrotron Radiation Facility (ESRF). Depression of 3rd harmonic radiation is significantly improved over the ESRF QPU, as deduced from the measured magnetic fields. A method of configuring shims of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1403.2504v1-abstract-full').style.display = 'inline'; document.getElementById('1403.2504v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1403.2504v1-abstract-full" style="display: none;"> China's first quasi-periodic undulator (QPU) has been developed for the Hefei Light Source (HLS). It uses a magnetic configuration with varied thicknesses of NdFeB blocks, based on the QPU of European Synchrotron Radiation Facility (ESRF). Depression of 3rd harmonic radiation is significantly improved over the ESRF QPU, as deduced from the measured magnetic fields. A method of configuring shims of different geometries and sizes, based on a symmetric principle to correct multi-pole field integrals, was demonstrated. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1403.2504v1-abstract-full').style.display = 'none'; document.getElementById('1403.2504v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 March, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">4 pages, 6 figures, 2 tables</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1308.5025">arXiv:1308.5025</a> <span> [<a href="https://arxiv.org/pdf/1308.5025">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Instrumentation and Detectors">physics.ins-det</span> </div> </div> <p class="title is-5 mathjax"> Development of A Modified Quasi-periodic Undulator for HLS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Yang%2C+Y">Yufeng Yang</a>, <a href="/search/physics?searchtype=author&query=Lu%2C+H">Huihua Lu</a>, <a href="/search/physics?searchtype=author&query=chen%2C+W">Wan chen</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a>, <a href="/search/physics?searchtype=author&query=Sun%2C+S">Shuchen Sun</a>, <a href="/search/physics?searchtype=author&query=Li%2C+Z">Zhiqiang Li</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1308.5025v1-abstract-short" style="display: inline;"> A modified quasi periodic undulator (QPU) is developed and to be installed at Hefei Light Source (HLS).Magnet dimensions optimization is applied. High harmonics contamination is eliminated from the fundamental emission effectively according to the field tests. The depression ratio of 3rd harmonic is increased by an order of magnitude than the current device with other harmonics well reduced simult… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1308.5025v1-abstract-full').style.display = 'inline'; document.getElementById('1308.5025v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1308.5025v1-abstract-full" style="display: none;"> A modified quasi periodic undulator (QPU) is developed and to be installed at Hefei Light Source (HLS).Magnet dimensions optimization is applied. High harmonics contamination is eliminated from the fundamental emission effectively according to the field tests. The depression ratio of 3rd harmonic is increased by an order of magnitude than the current device with other harmonics well reduced simultaneously. The significance of the modification measure is verified practically. The design, measurement and commissioning of the device is described. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1308.5025v1-abstract-full').style.display = 'none'; document.getElementById('1308.5025v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 August, 2013; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2013. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 5 figures, 4 tables</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1306.0951">arXiv:1306.0951</a> <span> [<a href="https://arxiv.org/pdf/1306.0951">pdf</a>, <a href="https://arxiv.org/ps/1306.0951">ps</a>, <a href="https://arxiv.org/format/1306.0951">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/38/5/057004">10.1088/1674-1137/38/5/057004 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Velocity bunching in travelling wave accelerator with low acceleration gradient </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Huang%2C+R">Rui-Xuan Huang</a>, <a href="/search/physics?searchtype=author&query=He%2C+Z">Zhi-Gang He</a>, <a href="/search/physics?searchtype=author&query=Li%2C+W">Wei-Wei Li</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi-Ka Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1306.0951v1-abstract-short" style="display: inline;"> We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1306.0951v1-abstract-full').style.display = 'inline'; document.getElementById('1306.0951v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1306.0951v1-abstract-full" style="display: none;"> We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed electron beam with symmetrical longitudinal distribution and low energy spread. We also present a transverse emittance compensation scheme to compensate the emittance growth caused by the increasing of the space charge force in the compressing process that is easy to be adjusted for different compressing factors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1306.0951v1-abstract-full').style.display = 'none'; document.getElementById('1306.0951v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 4 June, 2013; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2013. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1305.4765">arXiv:1305.4765</a> <span> [<a href="https://arxiv.org/pdf/1305.4765">pdf</a>, <a href="https://arxiv.org/ps/1305.4765">ps</a>, <a href="https://arxiv.org/format/1305.4765">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/37/12/127002">10.1088/1674-1137/37/12/127002 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Generation and measurement of sub-picosecond electron bunch in photocathode rf gun </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Li%2C+W">Weiwei Li</a>, <a href="/search/physics?searchtype=author&query=He%2C+Z">Zhiagng He</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qika Jia</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1305.4765v1-abstract-short" style="display: inline;"> We consider a scheme to generate sub-picosecond electron bunch in the photocathode rf gun by improving the acceleration gradient in the gun, suitably tuning the bunch charge, the laser spot size and the acceleration phase, and reducing the growth of transverse emittance by laser shaping. A nondestructive technique is also reported to measure the electron bunch length, by measuring the high-frequen… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1305.4765v1-abstract-full').style.display = 'inline'; document.getElementById('1305.4765v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1305.4765v1-abstract-full" style="display: none;"> We consider a scheme to generate sub-picosecond electron bunch in the photocathode rf gun by improving the acceleration gradient in the gun, suitably tuning the bunch charge, the laser spot size and the acceleration phase, and reducing the growth of transverse emittance by laser shaping. A nondestructive technique is also reported to measure the electron bunch length, by measuring the high-frequency spectrum of wakefield radiation which is caused by the passage of a relativistic electron bunch through a channel surrounded by a dielectric. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1305.4765v1-abstract-full').style.display = 'none'; document.getElementById('1305.4765v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 21 May, 2013; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2013. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1305.0694">arXiv:1305.0694</a> <span> [<a href="https://arxiv.org/pdf/1305.0694">pdf</a>, <a href="https://arxiv.org/ps/1305.0694">ps</a>, <a href="https://arxiv.org/format/1305.0694">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Accelerator Physics">physics.acc-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Nuclear Theory">nucl-th</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1674-1137/37/6/068101">10.1088/1674-1137/37/6/068101 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Harmonics suppression effect of the quasi-periodic undulator in SASE free-electron-laser </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Wu%2C+A">Ai-Lin Wu</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qi-Ka Jia</a>, <a href="/search/physics?searchtype=author&query=Li%2C+H">He-Ting Li</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1305.0694v1-abstract-short" style="display: inline;"> In this paper, the harmonics suppression effect of QPUs in SASE FEL is investigated. The numerical results show that the harmonics power is reduced by using QPUs, but the fundamental radiation power also has a pronounced decrease as the saturation length gets very long. The cases of employing QPUs as parts of undulators are studied. The calculations show that if the fraction of QPUs and their offg… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1305.0694v1-abstract-full').style.display = 'inline'; document.getElementById('1305.0694v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1305.0694v1-abstract-full" style="display: none;"> In this paper, the harmonics suppression effect of QPUs in SASE FEL is investigated. The numerical results show that the harmonics power is reduced by using QPUs, but the fundamental radiation power also has a pronounced decrease as the saturation length gets very long. The cases of employing QPUs as parts of undulators are studied. The calculations show that if the fraction of QPUs and their offgap are appropriate in an undulator system, the harmonics radiation could be suppressed remarkably, meanwhile the fundamental saturation length does not increase too much. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1305.0694v1-abstract-full').style.display = 'none'; document.getElementById('1305.0694v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 3 May, 2013; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2013. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1209.6629">arXiv:1209.6629</a> <span> [<a href="https://arxiv.org/pdf/1209.6629">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Chemical Physics">physics.chem-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> </div> <p class="title is-5 mathjax"> Evaluating the role of Lead In A Novel Ternary Catalysts For DMFCs </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Halder%2C+A">Aditi Halder</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q">Qingying Jia</a>, <a href="/search/physics?searchtype=author&query=Trahan%2C+M">Matthew Trahan</a>, <a href="/search/physics?searchtype=author&query=Mukerjee%2C+S">Sanjeev Mukerjee</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1209.6629v1-abstract-short" style="display: inline;"> The current density at lower potential is highly desirable in fuel cell technology and crucial center point for designing a new catalyst. By alloying platinum with various other metals, the improvisation of the fuel cell catalyst has achieved a lot of attention and interests. In this article, a novel porous ternary alloy PtPb@Ru as anode catalysts for direct methanol fuel cell had been synthesized… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1209.6629v1-abstract-full').style.display = 'inline'; document.getElementById('1209.6629v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1209.6629v1-abstract-full" style="display: none;"> The current density at lower potential is highly desirable in fuel cell technology and crucial center point for designing a new catalyst. By alloying platinum with various other metals, the improvisation of the fuel cell catalyst has achieved a lot of attention and interests. In this article, a novel porous ternary alloy PtPb@Ru as anode catalysts for direct methanol fuel cell had been synthesized by micro-emulsion technique. The catalysts had been characterized by various spectroscopic and microscopic techniques. The activity and durability of the catalysts had been tested by running cyclic voltammetry in 0.1 M HClO4 and 1M Methanol. To explain the many fold increase in current density of the PtPb@Ru catalysts in comparison to the commercial available PtRu catalysts, in situ X-ray absorption spectroscopy (XAS) measurements, at the PtL3 edge (XANES and EXAFS) were carried out on the PtPb@Ru catalysts in an electrochemical cell. The down-shift in the d-band center of platinum observed in the XAS study, might be responsible for the better activity and high current density observed here. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1209.6629v1-abstract-full').style.display = 'none'; document.getElementById('1209.6629v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 28 September, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2012. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">19 pages, 7 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1102.3507">arXiv:1102.3507</a> <span> [<a href="https://arxiv.org/pdf/1102.3507">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OL.36.001230">10.1364/OL.36.001230 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Thermal tunability in terahertz metamaterials fabricated on strontium titanate single crystal substrates </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Singh%2C+R">Ranjan Singh</a>, <a href="/search/physics?searchtype=author&query=Azad%2C+A+K">Abul K. Azad</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q+X">Q. X. Jia</a>, <a href="/search/physics?searchtype=author&query=Taylor%2C+A+J">Antoinette J. Taylor</a>, <a href="/search/physics?searchtype=author&query=Chen%2C+H">Hou-Tong Chen</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1102.3507v1-abstract-short" style="display: inline;"> We report an experimental demonstration of thermal tuning of resonance frequency in a planar terahertz metamaterial consisting of a gold split-ring resonator array fabricated on a bulk single crystal strontium titanate (SrTiO3) substrate. Cooling the metamaterial starting from 409 K down to 150 K causes about 50% shift in resonance frequency as compare to its room temperature resonance, and there… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1102.3507v1-abstract-full').style.display = 'inline'; document.getElementById('1102.3507v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1102.3507v1-abstract-full" style="display: none;"> We report an experimental demonstration of thermal tuning of resonance frequency in a planar terahertz metamaterial consisting of a gold split-ring resonator array fabricated on a bulk single crystal strontium titanate (SrTiO3) substrate. Cooling the metamaterial starting from 409 K down to 150 K causes about 50% shift in resonance frequency as compare to its room temperature resonance, and there is very little variation in resonance strength. The resonance shift is due to the temperature-dependent refractive index (or the dielectric constant) of the strontium titanate. The experiment opens up avenues for designing tunable terahertz devices by exploiting the temperature sensitive characteristic of high dielectric constant substrates and complex metal oxide materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1102.3507v1-abstract-full').style.display = 'none'; document.getElementById('1102.3507v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 17 February, 2011; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2011. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 3 figures, accepted at Optics Letters</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1009.1640">arXiv:1009.1640</a> <span> [<a href="https://arxiv.org/pdf/1009.1640">pdf</a>, <a href="https://arxiv.org/format/1009.1640">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.105.247402">10.1103/PhysRevLett.105.247402 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Tuning the Resonance in High Temperature Superconducting Terahertz Metamaterials </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Chen%2C+H">Hou-Tong Chen</a>, <a href="/search/physics?searchtype=author&query=Yang%2C+H">Hao Yang</a>, <a href="/search/physics?searchtype=author&query=Singh%2C+R">Ranjan Singh</a>, <a href="/search/physics?searchtype=author&query=O%27Hara%2C+J+F">John F. O'Hara</a>, <a href="/search/physics?searchtype=author&query=Azad%2C+A+K">Abul K. Azad</a>, <a href="/search/physics?searchtype=author&query=Trugman%2C+S+A">Stuart A. Trugman</a>, <a href="/search/physics?searchtype=author&query=Jia%2C+Q+X">Q. X. Jia</a>, <a href="/search/physics?searchtype=author&query=Taylor%2C+A+J">Antoinette J. Taylor</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1009.1640v1-abstract-short" style="display: inline;"> In this Letter we present resonance properties in terahertz metamaterials consisting of a split-ring resonator array made from high temperature superconducting films. By varying the temperature, we observed efficient metamaterial resonance switching and frequency tuning with some features not revealed before. The results were well reproduced by numerical simulations of metamaterial resonance using… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1009.1640v1-abstract-full').style.display = 'inline'; document.getElementById('1009.1640v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1009.1640v1-abstract-full" style="display: none;"> In this Letter we present resonance properties in terahertz metamaterials consisting of a split-ring resonator array made from high temperature superconducting films. By varying the temperature, we observed efficient metamaterial resonance switching and frequency tuning with some features not revealed before. The results were well reproduced by numerical simulations of metamaterial resonance using the experimentally measured complex conductivity of the superconducting film. We developed a theoretical model that explains the tuning features, which takes into account the resistive resonance damping and additional split-ring inductance contributed from both the real and imaginary parts of the temperature-dependent complex conductivity. The theoretical model further predicted more efficient resonance switching and frequency shifting in metamaterials consisting of a thinner superconducting split-ring resonator array, which were also verified in experiments. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1009.1640v1-abstract-full').style.display = 'none'; document.getElementById('1009.1640v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 8 September, 2010; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2010. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 3 figures, submitted to Physical Review Letters</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review Letters 105, 247402 (2010) </p> </li> </ol> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous is-invisible">Previous </a> <a href="/search/?searchtype=author&query=Jia%2C+Q&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Jia%2C+Q&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Jia%2C+Q&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> </ul> </nav> <div class="is-hidden-tablet">  <span class="help" style="display: inline-block;"><a href="https://github.com/arXiv/arxiv-search/releases">Search v0.5.6 released 2020-02-24</a>  </span> </div> </div> </main> <footer> <div class="columns is-desktop" role="navigation" aria-label="Secondary">  <div class="column"> <div class="columns"> 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