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abstracts</label></li><li><input id="abstracts-1" name="abstracts" type="radio" value="hide"> <label for="abstracts-1">Hide abstracts</label></li></ul> </div> <div class="box field is-grouped is-grouped-multiline level-item"> <div class="control"> <span class="select is-small"> <select id="size" name="size"><option value="25">25</option><option selected value="50">50</option><option value="100">100</option><option value="200">200</option></select> </span> <label for="size">results per page</label>. </div> <div class="control"> <label for="order">Sort results by</label> <span class="select is-small"> <select id="order" name="order"><option selected value="-announced_date_first">Announcement date (newest first)</option><option value="announced_date_first">Announcement date (oldest first)</option><option value="-submitted_date">Submission date (newest first)</option><option value="submitted_date">Submission date (oldest first)</option><option value="">Relevance</option></select> </span> </div> <div class="control"> <button class="button is-small is-link">Go</button> </div> </div> </form> </div> </div> <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/2410.00973">arXiv:2410.00973</a> <span> [<a href="https://arxiv.org/pdf/2410.00973">pdf</a>, <a href="https://arxiv.org/format/2410.00973">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Gases">cond-mat.quant-gas</span> </div> </div> <p class="title is-5 mathjax"> Multi-site gates for state preparation in quantum simulation of the Bose Hubbard Model </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Praneel%2C+P">Pranjal Praneel</a>, <a href="/search/cond-mat?searchtype=author&query=Kiely%2C+T+G">Thomas G. Kiely</a>, <a href="/search/cond-mat?searchtype=author&query=Mueller%2C+E+J">Erich J. Mueller</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">Andre G. Petukhov</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="2410.00973v2-abstract-short" style="display: inline;"> We construct a sequence of multi-site gates which transform an easily constructed product state into an approximation to the superfluid ground state of the Bose-Hubbard model. The mapping is exact in the one dimensional hard core limit, and for non-interacting particles in both one and two dimensions. The gate sequence has other applications, such as being used as part of a many-body interferomete… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.00973v2-abstract-full').style.display = 'inline'; document.getElementById('2410.00973v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2410.00973v2-abstract-full" style="display: none;"> We construct a sequence of multi-site gates which transform an easily constructed product state into an approximation to the superfluid ground state of the Bose-Hubbard model. The mapping is exact in the one dimensional hard core limit, and for non-interacting particles in both one and two dimensions. The gate sequence has other applications, such as being used as part of a many-body interferometer which probes the existence of doublons. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.00973v2-abstract-full').style.display = 'none'; document.getElementById('2410.00973v2-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> 26 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 1 October, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">12 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/2207.01740">arXiv:2207.01740</a> <span> [<a href="https://arxiv.org/pdf/2207.01740">pdf</a>, <a href="https://arxiv.org/format/2207.01740">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</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/10.1103/PhysRevApplied.19.064066">10.1103/PhysRevApplied.19.064066 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Characterizing low-frequency qubit noise </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wudarski%2C+F">Filip Wudarski</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yaxing Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Korotkov%2C+A">Alexander Korotkov</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Dykman%2C+M+I">M. I. Dykman</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="2207.01740v1-abstract-short" style="display: inline;"> Fluctuations of the qubit frequencies are one of the major problems to overcome on the way to scalable quantum computers. Of particular importance are fluctuations with the correlation time that exceeds the decoherence time due to decay and dephasing by fast processes. The statistics of the fluctuations can be characterized by measuring the correlators of the outcomes of periodically repeated Rams… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2207.01740v1-abstract-full').style.display = 'inline'; document.getElementById('2207.01740v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2207.01740v1-abstract-full" style="display: none;"> Fluctuations of the qubit frequencies are one of the major problems to overcome on the way to scalable quantum computers. Of particular importance are fluctuations with the correlation time that exceeds the decoherence time due to decay and dephasing by fast processes. The statistics of the fluctuations can be characterized by measuring the correlators of the outcomes of periodically repeated Ramsey measurements. This work suggests a method that allows describing qubit dynamics during repeated measurements in the presence of evolving noise. It made it possible, in particular, to evaluate the two-time correlator for the noise from two-level systems and obtain two- and three-time correlators for a Gaussian noise. The explicit expressions for the correlators are compared with simulations. A significant difference of the three-time correlators for the noise from two-level systems and for a Gaussian noise is demonstrated. Strong broadening of the distribution of the outcomes of Ramsey measurements, with a possible fine structure, is found for the data acquisition time comparable to the noise correlation time. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2207.01740v1-abstract-full').style.display = 'none'; document.getElementById('2207.01740v1-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 July, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2003.14244">arXiv:2003.14244</a> <span> [<a href="https://arxiv.org/pdf/2003.14244">pdf</a>, <a href="https://arxiv.org/format/2003.14244">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> </div> </div> <p class="title is-5 mathjax"> Probing Environmental Spin Polarization with Superconducting Flux Qubits </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Lanting%2C+T">T. Lanting</a>, <a href="/search/cond-mat?searchtype=author&query=Amin%2C+M+H">M. H. Amin</a>, <a href="/search/cond-mat?searchtype=author&query=Baron%2C+C">C. Baron</a>, <a href="/search/cond-mat?searchtype=author&query=Babcock%2C+M">M. Babcock</a>, <a href="/search/cond-mat?searchtype=author&query=Boschee%2C+J">J. Boschee</a>, <a href="/search/cond-mat?searchtype=author&query=Boixo%2C+S">S. Boixo</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Foygel%2C+M">M. Foygel</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="2003.14244v2-abstract-short" style="display: inline;"> We present measurements of the dynamics of a polarized magnetic environment coupled to the flux degree of freedom of rf-SQUID flux qubits. The qubits are used as both sources of polarizing field and detectors of the environmental polarization. We probe dynamics at timescales from 5 $渭$s to 5 ms and at temperatures between 12.5 and 22 mK. The measured polarization versus temperature provides strong… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2003.14244v2-abstract-full').style.display = 'inline'; document.getElementById('2003.14244v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2003.14244v2-abstract-full" style="display: none;"> We present measurements of the dynamics of a polarized magnetic environment coupled to the flux degree of freedom of rf-SQUID flux qubits. The qubits are used as both sources of polarizing field and detectors of the environmental polarization. We probe dynamics at timescales from 5 $渭$s to 5 ms and at temperatures between 12.5 and 22 mK. The measured polarization versus temperature provides strong evidence for a phase transition at a temperature of $5.7\pm 0.3$ mK. Furthermore, the environmental polarization grows initially as $\sqrt{t}$, consistent with spin diffusion dynamics. However, spin diffusion model deviates from data at long timescales, suggesting that a different phenomenon is responsible for the low-frequency behavior. A simple $1/f$ model can fit the data at all time scales but it requires empirical low- and high-frequency cutoffs. We argue that these results are consistent with an environment comprised of random clusters of spins, with fast spin diffusion dynamics within the clusters and slow fluctuations of the total moments of the clusters. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2003.14244v2-abstract-full').style.display = 'none'; document.getElementById('2003.14244v2-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 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 March, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">12 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/1901.06756">arXiv:1901.06756</a> <span> [<a href="https://arxiv.org/pdf/1901.06756">pdf</a>, <a href="https://arxiv.org/format/1901.06756">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> </div> </div> <p class="title is-5 mathjax"> Backflow Effect on Spin Diffusion Near Ferromagnet-Superconductor Interface </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Faiz%2C+M">M. Faiz</a>, <a href="/search/cond-mat?searchtype=author&query=Panguluri%2C+R+P">R. P. Panguluri</a>, <a href="/search/cond-mat?searchtype=author&query=Nadgorny%2C+B">B. Nadgorny</a>, <a href="/search/cond-mat?searchtype=author&query=Balke%2C+B">B. Balke</a>, <a href="/search/cond-mat?searchtype=author&query=Wurmehl%2C+S">S. Wurmehl</a>, <a href="/search/cond-mat?searchtype=author&query=Felser%2C+C">C. Felser</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="1901.06756v1-abstract-short" style="display: inline;"> The behavior of spin propagation in metals in various measurement schemes is shown to be qualitatively different than a simple exponential decay - due to the backflow effect on spin diffusion in the presence of interfaces. To probe this effect we utilize the spin sensitivity of an Andreev contact between gold films of variable thickness deposited on top of a spin injector, Co$_{2}$Mn$_{0.5}$Fe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.06756v1-abstract-full').style.display = 'inline'; document.getElementById('1901.06756v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1901.06756v1-abstract-full" style="display: none;"> The behavior of spin propagation in metals in various measurement schemes is shown to be qualitatively different than a simple exponential decay - due to the backflow effect on spin diffusion in the presence of interfaces. To probe this effect we utilize the spin sensitivity of an Andreev contact between gold films of variable thickness deposited on top of a spin injector, Co$_{2}$Mn$_{0.5}$Fe$_{0.5}$Si, with the spin polarization of approximately 45\%, and Nb superconducting tip. While the results are consistent with gradually decaying spin polarization as the film thickness increases, the spin diffusion length in Au found to be 285 nm, is more than two times larger that one would have obtained without taking the backflow effect into account. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.06756v1-abstract-full').style.display = 'none'; document.getElementById('1901.06756v1-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 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2019. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1711.05320">arXiv:1711.05320</a> <span> [<a href="https://arxiv.org/pdf/1711.05320">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> </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/PhysRevMaterials.2.014406">10.1103/PhysRevMaterials.2.014406 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Growth, electrical, structural, and magnetic properties of half-Heusler CoTi$_{1-x}$Fe$_x$Sb </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Harrington%2C+S+D">Sean D. Harrington</a>, <a href="/search/cond-mat?searchtype=author&query=Rice%2C+A+D">Anthony D. Rice</a>, <a href="/search/cond-mat?searchtype=author&query=Brown-Heft%2C+T">Tobias Brown-Heft</a>, <a href="/search/cond-mat?searchtype=author&query=Bonef%2C+B">Bastien Bonef</a>, <a href="/search/cond-mat?searchtype=author&query=Sharan%2C+A">Abhishek Sharan</a>, <a href="/search/cond-mat?searchtype=author&query=McFadden%2C+A+P">Anthony P. McFadden</a>, <a href="/search/cond-mat?searchtype=author&query=Logan%2C+J+A">John A. Logan</a>, <a href="/search/cond-mat?searchtype=author&query=Pendharkar%2C+M">Mihir Pendharkar</a>, <a href="/search/cond-mat?searchtype=author&query=Feldman%2C+M+M">Mayer M. Feldman</a>, <a href="/search/cond-mat?searchtype=author&query=Mercan%2C+O">Ozge Mercan</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">Andre G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Janotti%2C+A">Anderson Janotti</a>, <a href="/search/cond-mat?searchtype=author&query=Arslan%2C+L+%C3%87">Leyla 脟olakerol Arslan</a>, <a href="/search/cond-mat?searchtype=author&query=Palmstr%C3%B8m%2C+C+J">Chris J. Palmstr酶m</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="1711.05320v1-abstract-short" style="display: inline;"> Epitaxial thin films of the substitutionally alloyed half-Heusler series CoTi$_{1-x}$Fe$_x$Sb were grown by molecular beam epitaxy on InAlAs/InP(001) substrates for concentrations 0.0$\leq$x$\leq$1.0. The influence of Fe on the structural, electronic, and magnetic properties was studied and compared to that expected from density functional theory. The films are epitaxial and single crystalline, as… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.05320v1-abstract-full').style.display = 'inline'; document.getElementById('1711.05320v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1711.05320v1-abstract-full" style="display: none;"> Epitaxial thin films of the substitutionally alloyed half-Heusler series CoTi$_{1-x}$Fe$_x$Sb were grown by molecular beam epitaxy on InAlAs/InP(001) substrates for concentrations 0.0$\leq$x$\leq$1.0. The influence of Fe on the structural, electronic, and magnetic properties was studied and compared to that expected from density functional theory. The films are epitaxial and single crystalline, as measured by reflection high-energy electron diffraction and X-ray diffraction. Using in-situ X-ray photoelectron spectroscopy, only small changes in the valence band are detected for x$\leq$0.5. For films with x$\geq$0.05, ferromagnetism is observed in SQUID magnetometry with a saturation magnetization that scales linearly with Fe content. A dramatic decrease in the magnetic moment per formula unit occurs when the Fe is substitutionally alloyed on the Co site indicating a strong dependence on the magnetic moment with site occupancy. A crossover from both in-plane and out-of-plane magnetic moments to only in-plane moment occurs for higher concentrations of Fe. Ferromagnetic resonance indicates a transition from weak to strong interaction with a reduction in inhomogeneous broadening as Fe content is increased. Temperature-dependent transport reveals a semiconductor to metal transition with thermally activated behavior for x$\leq$0.5. Anomalous Hall effect and large negative magnetoresistance (up to -18.5% at 100 kOe for x=0.3) are observed for higher Fe content films. Evidence of superparamagnetism for x=0.3 and x=0.2 suggests for moderate levels of Fe, demixing of the CoTi$_{1-x}$Fe$_x$Sb films into Fe rich and Fe deficient regions may be present. Atom probe tomography is used to examine the Fe distribution in a x=0.3 film. Statistical analysis reveals a nonhomogeneous distribution of Fe atoms throughout the film, which is used to explain the observed magnetic and electrical behavior. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.05320v1-abstract-full').style.display = 'none'; document.getElementById('1711.05320v1-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> 14 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Materials 2, 014406 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1707.01565">arXiv:1707.01565</a> <span> [<a href="https://arxiv.org/pdf/1707.01565">pdf</a>, <a href="https://arxiv.org/format/1707.01565">other</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> </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/10.12693/APhysPolA.133.343">10.12693/APhysPolA.133.343 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Multiband Electronic Structure of Magnetic Quantum Dots: Numerical Studies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Rederth%2C+D">D. Rederth</a>, <a href="/search/cond-mat?searchtype=author&query=Oszwaldowski%2C+R">R. Oszwaldowski</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Pientka%2C+J">J. Pientka</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="1707.01565v1-abstract-short" style="display: inline;"> Semiconductor quantum dots (QDs) doped with magnetic impurities have been a focus of continuous research for a couple of decades. A significant effort has been devoted to studies of magnetic polarons (MP) in these nanostructures. These collective states arise through exchange interaction between a carrier confined in a QD and localized spins of the magnetic impurities (typically: Mn). We discuss o… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.01565v1-abstract-full').style.display = 'inline'; document.getElementById('1707.01565v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1707.01565v1-abstract-full" style="display: none;"> Semiconductor quantum dots (QDs) doped with magnetic impurities have been a focus of continuous research for a couple of decades. A significant effort has been devoted to studies of magnetic polarons (MP) in these nanostructures. These collective states arise through exchange interaction between a carrier confined in a QD and localized spins of the magnetic impurities (typically: Mn). We discuss our theoretical description of various MP properties in self-assembled QDs. We present a self-consistent, temperature-dependent approach to MPs formed by a valence band hole. We use the Luttinger-Kohn k.p Hamiltonian to account for the important effects of spin-orbit interaction. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.01565v1-abstract-full').style.display = 'none'; document.getElementById('1707.01565v1-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 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 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">7 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/1608.08752">arXiv:1608.08752</a> <span> [<a href="https://arxiv.org/pdf/1608.08752">pdf</a>, <a href="https://arxiv.org/format/1608.08752">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</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/10.1103/PhysRevLett.118.057702">10.1103/PhysRevLett.118.057702 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Observation of classical-quantum crossover of 1/f flux noise and its paramagnetic temperature dependence </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Quintana%2C+C+M">C. M. Quintana</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Y">Yu Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Sank%2C+D">D. Sank</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=White%2C+T+C">T. C. White</a>, <a href="/search/cond-mat?searchtype=author&query=Kafri%2C+D">Dvir Kafri</a>, <a href="/search/cond-mat?searchtype=author&query=Chiaro%2C+B">B. Chiaro</a>, <a href="/search/cond-mat?searchtype=author&query=Megrant%2C+A">A. Megrant</a>, <a href="/search/cond-mat?searchtype=author&query=Barends%2C+R">R. Barends</a>, <a href="/search/cond-mat?searchtype=author&query=Campbell%2C+B">B. Campbell</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Z">Z. Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Dunsworth%2C+A">A. Dunsworth</a>, <a href="/search/cond-mat?searchtype=author&query=Fowler%2C+A+G">A. G. Fowler</a>, <a href="/search/cond-mat?searchtype=author&query=Graff%2C+R">R. Graff</a>, <a href="/search/cond-mat?searchtype=author&query=Jeffrey%2C+E">E. Jeffrey</a>, <a href="/search/cond-mat?searchtype=author&query=Kelly%2C+J">J. Kelly</a>, <a href="/search/cond-mat?searchtype=author&query=Lucero%2C+E">E. Lucero</a>, <a href="/search/cond-mat?searchtype=author&query=Mutus%2C+J+Y">J. Y. Mutus</a>, <a href="/search/cond-mat?searchtype=author&query=Neeley%2C+M">M. Neeley</a>, <a href="/search/cond-mat?searchtype=author&query=Neill%2C+C">C. Neill</a>, <a href="/search/cond-mat?searchtype=author&query=O%27Malley%2C+P+J+J">P. J. J. O'Malley</a>, <a href="/search/cond-mat?searchtype=author&query=Roushan%2C+P">P. Roushan</a>, <a href="/search/cond-mat?searchtype=author&query=Shabani%2C+A">A. Shabani</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Vainsencher%2C+A">A. Vainsencher</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="1608.08752v2-abstract-short" style="display: inline;"> By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides of its two-sided environmental flux noise spectral density over a range of frequencies around $2k_BT/h \approx 1\,\rm{GHz}$, allowing for the observation of a classical-quantum crossover. Below the crossover point, the symmetric noise component follows a $1/f$ power law that matches the magnitude of the $1/f$… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.08752v2-abstract-full').style.display = 'inline'; document.getElementById('1608.08752v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1608.08752v2-abstract-full" style="display: none;"> By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides of its two-sided environmental flux noise spectral density over a range of frequencies around $2k_BT/h \approx 1\,\rm{GHz}$, allowing for the observation of a classical-quantum crossover. Below the crossover point, the symmetric noise component follows a $1/f$ power law that matches the magnitude of the $1/f$ noise near $1\,{\rm{Hz}}$. The antisymmetric component displays a 1/T dependence below $100\,\rm{mK}$, providing dynamical evidence for a paramagnetic environment. Extrapolating the two-sided spectrum predicts the linewidth and reorganization energy of incoherent resonant tunneling between flux qubit wells. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.08752v2-abstract-full').style.display = 'none'; document.getElementById('1608.08752v2-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 September, 2016; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 August, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 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">paper + supplement</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 118, 057702 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1510.04376">arXiv:1510.04376</a> <span> [<a href="https://arxiv.org/pdf/1510.04376">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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/10.1103/PhysRevB.92.035430">10.1103/PhysRevB.92.035430 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Time-resolved magnetophotoluminescence studies of magnetic polaron dynamics in type-II quantum dots </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Barman%2C+B">B. Barman</a>, <a href="/search/cond-mat?searchtype=author&query=Oszwa%C5%82dowski%2C+R">R. Oszwa艂dowski</a>, <a href="/search/cond-mat?searchtype=author&query=Schweidenback%2C+L">L. Schweidenback</a>, <a href="/search/cond-mat?searchtype=author&query=Russ%2C+A+H">A. H. Russ</a>, <a href="/search/cond-mat?searchtype=author&query=Pientka%2C+J+M">J. M. Pientka</a>, <a href="/search/cond-mat?searchtype=author&query=Tsai%2C+Y">Y. Tsai</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+W">W-C. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Fan%2C+W+C">W. C. Fan</a>, <a href="/search/cond-mat?searchtype=author&query=Murphy%2C+J+R">J. R. Murphy</a>, <a href="/search/cond-mat?searchtype=author&query=Cartwright%2C+A+N">A. N. Cartwright</a>, <a href="/search/cond-mat?searchtype=author&query=Sellers%2C+I+R">I. R. Sellers</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=%C5%BDuti%C4%87%2C+I">I. 沤uti膰</a>, <a href="/search/cond-mat?searchtype=author&query=McCombe%2C+B+D">B. D. McCombe</a>, <a href="/search/cond-mat?searchtype=author&query=Petrou%2C+A">A. Petrou</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="1510.04376v1-abstract-short" style="display: inline;"> We used continuous wave photoluminescence (cw-PL) and time resolved photoluminescence (TR-PL) spectroscopy to compare the properties of magnetic polarons (MP) in two related spatially indirect II-VI epitaxially grown quantum dot systems. In the ZnTe/(Zn,Mn)Se system the holes are confined in the non-magnetic ZnTe quantum dots (QDs), and the electrons reside in the magnetic (Zn,Mn)Se matrix. On the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1510.04376v1-abstract-full').style.display = 'inline'; document.getElementById('1510.04376v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1510.04376v1-abstract-full" style="display: none;"> We used continuous wave photoluminescence (cw-PL) and time resolved photoluminescence (TR-PL) spectroscopy to compare the properties of magnetic polarons (MP) in two related spatially indirect II-VI epitaxially grown quantum dot systems. In the ZnTe/(Zn,Mn)Se system the holes are confined in the non-magnetic ZnTe quantum dots (QDs), and the electrons reside in the magnetic (Zn,Mn)Se matrix. On the other hand, in the (Zn,Mn)Te/ZnSe system, the holes are confined in the magnetic (Zn,Mn)Te QDs, while the electrons remain in the surrounding non-magnetic ZnSe matrix. The magnetic polaron formation energies in both systems were measured from the temporal red-shift of the band-edge emission. The magnetic polaron exhibits distinct characteristics depending on the location of the Mn ions. In the ZnTe/(Zn,Mn)Se system the magnetic polaron shows conventional behavior with decreasing with increasing temperature T and increasing magnetic field B. In contrast, in the (Zn,Mn)Te/ZnSe system has unconventional dependence on temperature T and magnetic field B; is weakly dependent on T as well as on B. We discuss a possible origin for such a striking difference in the MP properties in two closely related QD systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1510.04376v1-abstract-full').style.display = 'none'; document.getElementById('1510.04376v1-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> 14 October, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">27 pages, 12 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> PhysRevB.92.035430(2015) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1509.05068">arXiv:1509.05068</a> <span> [<a href="https://arxiv.org/pdf/1509.05068">pdf</a>, <a href="https://arxiv.org/ps/1509.05068">ps</a>, <a href="https://arxiv.org/format/1509.05068">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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/10.1103/PhysRevB.92.155402">10.1103/PhysRevB.92.155402 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magnetic ordering in quantum dots: Open vs. closed shells </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Pientka%2C+J+M">J. M. Pientka</a>, <a href="/search/cond-mat?searchtype=author&query=Oszwa%C5%82dowski%2C+R">R. Oszwa艂dowski</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Han%2C+J+E">J. E. Han</a>, <a href="/search/cond-mat?searchtype=author&query=%C5%BDuti%C4%87%2C+I">Igor 沤uti膰</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="1509.05068v1-abstract-short" style="display: inline;"> In magnetically-doped quantum dots changing the carrier occupancy, from open to closed shells, leads to qualitatively different forms of carrier-mediated magnetic ordering. While it is common to study such nanoscale magnets within a mean field approximation, excluding the spin fluctuations can mask important phenomena and lead to spurious thermodynamic phase transitions in small magnetic systems.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1509.05068v1-abstract-full').style.display = 'inline'; document.getElementById('1509.05068v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1509.05068v1-abstract-full" style="display: none;"> In magnetically-doped quantum dots changing the carrier occupancy, from open to closed shells, leads to qualitatively different forms of carrier-mediated magnetic ordering. While it is common to study such nanoscale magnets within a mean field approximation, excluding the spin fluctuations can mask important phenomena and lead to spurious thermodynamic phase transitions in small magnetic systems. By employing coarse-grained, variational, and Monte Carlo methods on singly and doubly occupied quantum dots to include spin fluctuations, we evaluate the relevance of the mean field description and distinguish different finite-size scaling in nanoscale magnets. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1509.05068v1-abstract-full').style.display = 'none'; document.getElementById('1509.05068v1-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> 16 September, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">Accepted Physical Review B 13 pages, 12 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/1409.6285">arXiv:1409.6285</a> <span> [<a href="https://arxiv.org/pdf/1409.6285">pdf</a>, <a href="https://arxiv.org/format/1409.6285">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Donor Spin Qubits in Ge-based Phononic Crystals </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Hafiychuk%2C+V+V">V. V. Hafiychuk</a>, <a href="/search/cond-mat?searchtype=author&query=Vasko%2C+F+T">F. T. Vasko</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="1409.6285v1-abstract-short" style="display: inline;"> We propose qubits based on shallow donor electron spins in germanium. Spin-orbit interaction for donor spins in germanium is in many orders of magnitude stronger than in silicon. In a uniform bulk material it leads to very short spin lifetimes. However the lifetime increases dramatically when the donor is placed into a quasi-2D phononic crystal and the energy of the Zeeman splitting is tuned to li… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1409.6285v1-abstract-full').style.display = 'inline'; document.getElementById('1409.6285v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1409.6285v1-abstract-full" style="display: none;"> We propose qubits based on shallow donor electron spins in germanium. Spin-orbit interaction for donor spins in germanium is in many orders of magnitude stronger than in silicon. In a uniform bulk material it leads to very short spin lifetimes. However the lifetime increases dramatically when the donor is placed into a quasi-2D phononic crystal and the energy of the Zeeman splitting is tuned to lie within a phonon bandgap. In this situation single phonon processes are suppressed by energy conservation. The remaining two-phonon decay channel is very slow. The Zeeman splitting within the gap can be fine tuned to induce a strong, long-range coupling between the spins of remote donors via exchange by virtual phonons. This, in turn, opens a very efficient way to manipulate the quits. We explore various geometries of phononic crystals in order to maximize the coherent qubit-qubit coupling while keeping the decay rate minimal. We find that phononic crystals with unit cell sizes of 100-150 nm are viable candidates for quantum computing applications and suggest several spin-resonance experiments to verify our theoretical predictions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1409.6285v1-abstract-full').style.display = 'none'; document.getElementById('1409.6285v1-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 September, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">18 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/1212.0168">arXiv:1212.0168</a> <span> [<a href="https://arxiv.org/pdf/1212.0168">pdf</a>, <a href="https://arxiv.org/ps/1212.0168">ps</a>, <a href="https://arxiv.org/format/1212.0168">other</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="Strongly Correlated Electrons">cond-mat.str-el</span> </div> </div> <p class="title is-5 mathjax"> On the half-metallicity of Co2FeSi Heusler alloy: an experimental and ab initio study </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Makinistian%2C+L">L. Makinistian</a>, <a href="/search/cond-mat?searchtype=author&query=Faiz%2C+M+M">Muhammad M. Faiz</a>, <a href="/search/cond-mat?searchtype=author&query=Panguluri%2C+R+P">Raghava P. Panguluri</a>, <a href="/search/cond-mat?searchtype=author&query=Balke%2C+B">B. Balke</a>, <a href="/search/cond-mat?searchtype=author&query=Wurmehl%2C+S">S. Wurmehl</a>, <a href="/search/cond-mat?searchtype=author&query=Felser%2C+C">C. Felser</a>, <a href="/search/cond-mat?searchtype=author&query=Albanesi%2C+E+A">E. A. Albanesi</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Nadgorny%2C+B">B. Nadgorny</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="1212.0168v1-abstract-short" style="display: inline;"> Co2FeSi, a Heusler alloy with the highest magnetic moment per unit cell and the highest Curie temperature, has largely been described theoretically as a half-metal. This conclusion, however, disagrees with Point Contact Andreev Reflection (PCAR) spectroscopy measurements, which give much lower values of spin polarization, P. Here, we present the spin polarization measurements of Co2FeSi by the PCA… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1212.0168v1-abstract-full').style.display = 'inline'; document.getElementById('1212.0168v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1212.0168v1-abstract-full" style="display: none;"> Co2FeSi, a Heusler alloy with the highest magnetic moment per unit cell and the highest Curie temperature, has largely been described theoretically as a half-metal. This conclusion, however, disagrees with Point Contact Andreev Reflection (PCAR) spectroscopy measurements, which give much lower values of spin polarization, P. Here, we present the spin polarization measurements of Co2FeSi by the PCAR technique, along with a thorough computational exploration, within the DFT and a GGA+U approach, of the Coulomb exchange U-parameters for Co and Fe atoms, taking into account spin-orbit coupling. We find that the orbital contribution (mo) to the total magnetic moment (mT) is significant, since it is at least 3 times greater than the experimental uncertainty of mT. Account of mo radically affects the acceptable values of U. Specifically, we find no values of U that would simultaneously satisfy the experimental values of the magnetic moment and result in the half-metallicity of Co2FeSi. On the other hand, the ranges of U that we report as acceptable are compatible with spin polarization measurements (ours and the ones found in the literature), which all are within approximately 40-60% range. Thus, based on reconciling experimental and computational results, we conclude that: a) spin-orbit coupling cannot be neglected in calculating Co2FeSi magnetic properties, and b) Co2FeSi Heusler alloy is not half-metallic. We believe that our approach can be applied to other Heusler alloys such as Co2FeAl. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1212.0168v1-abstract-full').style.display = 'none'; document.getElementById('1212.0168v1-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, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">5 pages, 3 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/1210.8164">arXiv:1210.8164</a> <span> [<a href="https://arxiv.org/pdf/1210.8164">pdf</a>, <a href="https://arxiv.org/ps/1210.8164">ps</a>, <a href="https://arxiv.org/format/1210.8164">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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="Other Condensed Matter">cond-mat.other</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/PhysRevB.88.045307">10.1103/PhysRevB.88.045307 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Large Stark Effect for Li Donor Spins in Si </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Pendo%2C+L">Luke Pendo</a>, <a href="/search/cond-mat?searchtype=author&query=Handberg%2C+E+M">E. M. Handberg</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="1210.8164v1-abstract-short" style="display: inline;"> We study the effect of a static electric field on lithium donor spins in silicon. The anisotropy of the effective mass leads to the anisotropy of the quadratic Stark susceptibility, which we determined using the Dalgarno-Lewis exact summation method. The theory is asymptotically exact in the field domain below Li-donor ionization threshold, relevant to the Stark-tuning electron spin resonance expe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1210.8164v1-abstract-full').style.display = 'inline'; document.getElementById('1210.8164v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1210.8164v1-abstract-full" style="display: none;"> We study the effect of a static electric field on lithium donor spins in silicon. The anisotropy of the effective mass leads to the anisotropy of the quadratic Stark susceptibility, which we determined using the Dalgarno-Lewis exact summation method. The theory is asymptotically exact in the field domain below Li-donor ionization threshold, relevant to the Stark-tuning electron spin resonance experiments. To obtain the generalized Stark susceptibilities at arbitrary fields, we propose a new variational wave function which reproduces the exact results in the low-field limit. With the calculated susceptibilities at hand, we are able to predict and analyze several important physical effects. First, we observe that the energy level shifts due to the quadratic Stark effect for Li donors in Si are equivalent to, and can be mapped onto, those produced by an external stress. Second, we demonstrate that the Stark effect anisotropy, combined with the unique valley-orbit splitting of a Li donor in Si, spin-orbit interaction and specially tuned external stress, may lead to a very strong modulation of the donor spin $g$-factor by the electric field. Third, we investigate the influence of random strains on the $g$-factor shifts and quantify the random strain limits and requirements to Si material purity necessary to observe the $g$-factor Stark shifts experimentally. Finally, we discuss possible implications of our results for quantum information processing with Li spin qubits in Si. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1210.8164v1-abstract-full').style.display = 'none'; document.getElementById('1210.8164v1-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, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2012. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1210.6422">arXiv:1210.6422</a> <span> [<a href="https://arxiv.org/pdf/1210.6422">pdf</a>, <a href="https://arxiv.org/ps/1210.6422">ps</a>, <a href="https://arxiv.org/format/1210.6422">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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="Strongly Correlated Electrons">cond-mat.str-el</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/PhysRevB.86.201408">10.1103/PhysRevB.86.201408 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Spin ordering in magnetic quantum dots: From core-halo to Wigner molecules </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Oszwa%C5%82dowski%2C+R">R. Oszwa艂dowski</a>, <a href="/search/cond-mat?searchtype=author&query=Stano%2C+P">P. Stano</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=%C5%BDuti%C4%87%2C+I">Igor 沤uti膰</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="1210.6422v2-abstract-short" style="display: inline;"> The interplay of confinement and Coulomb interactions in quantum dots can lead to strongly correlated phases differing qualitatively from the Fermi liquid behavior. We explore how the presence of magnetic impurities in quantum dots can provide additional opportunities to study correlation effects and the resulting ordering in carrier and impurity spin. By employing exact diagonalization we reveal… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1210.6422v2-abstract-full').style.display = 'inline'; document.getElementById('1210.6422v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1210.6422v2-abstract-full" style="display: none;"> The interplay of confinement and Coulomb interactions in quantum dots can lead to strongly correlated phases differing qualitatively from the Fermi liquid behavior. We explore how the presence of magnetic impurities in quantum dots can provide additional opportunities to study correlation effects and the resulting ordering in carrier and impurity spin. By employing exact diagonalization we reveal that seemingly simple two-carrier quantum dots lead to a rich phase diagram. We propose experiments to verify our predictions, in particular we discuss interband optical transitions as a function of temperature and magnetic field. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1210.6422v2-abstract-full').style.display = 'none'; document.getElementById('1210.6422v2-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> 14 December, 2012; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 23 October, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">5 pages, 5 figures + 4 pages of auxiliary material; published version</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 86, 201408(R) (2012) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1210.1162">arXiv:1210.1162</a> <span> [<a href="https://arxiv.org/pdf/1210.1162">pdf</a>, <a href="https://arxiv.org/ps/1210.1162">ps</a>, <a href="https://arxiv.org/format/1210.1162">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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/10.1103/PhysRevB.86.161403">10.1103/PhysRevB.86.161403 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Reentrant Formation of Magnetic Polarons in Quantum Dots </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Pientka%2C+J+M">J. M. Pientka</a>, <a href="/search/cond-mat?searchtype=author&query=Oszwa%C5%82dowski%2C+R">R. Oszwa艂dowski</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Han%2C+J+E">J. E. Han</a>, <a href="/search/cond-mat?searchtype=author&query=%C5%BDuti%C4%87%2C+I">Igor 沤uti膰</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="1210.1162v1-abstract-short" style="display: inline;"> We propose a model of magnetic polaron formation in semiconductor quantum dots doped with magnetic ions. A wetting layer serves as a reservoir of photo-generated holes, which can be trapped by the adjacent quantum dots. For certain hole densities, the temperature dependence of the magnetization induced by the trapped holes is reentrant: it disappears for some temperature range and reappears at hig… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1210.1162v1-abstract-full').style.display = 'inline'; document.getElementById('1210.1162v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1210.1162v1-abstract-full" style="display: none;"> We propose a model of magnetic polaron formation in semiconductor quantum dots doped with magnetic ions. A wetting layer serves as a reservoir of photo-generated holes, which can be trapped by the adjacent quantum dots. For certain hole densities, the temperature dependence of the magnetization induced by the trapped holes is reentrant: it disappears for some temperature range and reappears at higher temperatures. We demonstrate that this peculiar effect is not an artifact of the mean field approximation and persists after statistical spin fluctuations are accounted for. We predict fingerprints of reentrant magnetic polarons in photoluminescence spectra. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1210.1162v1-abstract-full').style.display = 'none'; document.getElementById('1210.1162v1-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 October, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">Accepted Physical Review B Rapid Communications 5 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 86, 161403(R) (2012) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1202.3145">arXiv:1202.3145</a> <span> [<a href="https://arxiv.org/pdf/1202.3145">pdf</a>, <a href="https://arxiv.org/ps/1202.3145">ps</a>, <a href="https://arxiv.org/format/1202.3145">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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="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/10.1103/PhysRevB.85.155312">10.1103/PhysRevB.85.155312 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magnetic anisotropies of quantum dots </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Vyborny%2C+K">Karel Vyborny</a>, <a href="/search/cond-mat?searchtype=author&query=Han%2C+J+E">J. E. Han</a>, <a href="/search/cond-mat?searchtype=author&query=Oszwaldowski%2C+R">Rafal Oszwaldowski</a>, <a href="/search/cond-mat?searchtype=author&query=Zutic%2C+I">Igor Zutic</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="1202.3145v1-abstract-short" style="display: inline;"> Magnetic anisotropies in quantum dots (QDs) doped with magnetic ions are discussed in terms of two frameworks: anisotropic $g$-factors and magnetocrystalline anisotropy energy. It is shown that even a simple model of zinc-blende p-doped QDs displays a rich diagram of magnetic anisotropies in the QD parameter space. Tuning the confinement allows to control magnetic easy axes in QDs in ways not avai… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1202.3145v1-abstract-full').style.display = 'inline'; document.getElementById('1202.3145v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1202.3145v1-abstract-full" style="display: none;"> Magnetic anisotropies in quantum dots (QDs) doped with magnetic ions are discussed in terms of two frameworks: anisotropic $g$-factors and magnetocrystalline anisotropy energy. It is shown that even a simple model of zinc-blende p-doped QDs displays a rich diagram of magnetic anisotropies in the QD parameter space. Tuning the confinement allows to control magnetic easy axes in QDs in ways not available for the better-studied bulk. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1202.3145v1-abstract-full').style.display = 'none'; document.getElementById('1202.3145v1-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> 14 February, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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">submitted to PRB</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 85, 155312 (2012) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1106.2346">arXiv:1106.2346</a> <span> [<a href="https://arxiv.org/pdf/1106.2346">pdf</a>, <a href="https://arxiv.org/ps/1106.2346">ps</a>, <a href="https://arxiv.org/format/1106.2346">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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="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/10.1103/PhysRevLett.106.177201">10.1103/PhysRevLett.106.177201 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magnetism in Closed-shell Quantum Dots: Emergence of Magnetic Bipolarons </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Oszwa%C5%82dowski%2C+R">R. Oszwa艂dowski</a>, <a href="/search/cond-mat?searchtype=author&query=%C5%BDuti%C4%87%2C+I">I. 沤uti膰</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="1106.2346v1-abstract-short" style="display: inline;"> Similar to atoms and nuclei, semiconductor quantum dots exhibit formation of shells. Predictions of magnetic behavior of the dots are often based on the shell occupancies. Thus, closed-shell quantum dots are assumed to be inherently nonmagnetic. Here, we propose a possibility of magnetism in such dots doped with magnetic impurities. On the example of the system of two interacting fermions, the sim… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1106.2346v1-abstract-full').style.display = 'inline'; document.getElementById('1106.2346v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1106.2346v1-abstract-full" style="display: none;"> Similar to atoms and nuclei, semiconductor quantum dots exhibit formation of shells. Predictions of magnetic behavior of the dots are often based on the shell occupancies. Thus, closed-shell quantum dots are assumed to be inherently nonmagnetic. Here, we propose a possibility of magnetism in such dots doped with magnetic impurities. On the example of the system of two interacting fermions, the simplest embodiment of the closed-shell structure, we demonstrate the emergence of a novel broken-symmetry ground state that is neither spin-singlet nor spin-triplet. We propose experimental tests of our predictions and the magnetic-dot structures to perform them. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1106.2346v1-abstract-full').style.display = 'none'; document.getElementById('1106.2346v1-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 June, 2011; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 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">4 pages, 4 figures; http://link.aps.org/doi/10.1103/PhysRevLett.106.177201; minor changes</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 106, 177201 (2011) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/0912.0138">arXiv:0912.0138</a> <span> [<a href="https://arxiv.org/pdf/0912.0138">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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/10.1103/PhysRevB.82.195320">10.1103/PhysRevB.82.195320 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Robust Magnetic Polarons in Type-II (Zn,Mn)Te Quantum Dots </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Sellers%2C+I+R">I. R. Sellers</a>, <a href="/search/cond-mat?searchtype=author&query=Oszwaldowski%2C+R">R. Oszwaldowski</a>, <a href="/search/cond-mat?searchtype=author&query=Whiteside%2C+V+R">V. R. Whiteside</a>, <a href="/search/cond-mat?searchtype=author&query=Eginligil%2C+M">M. Eginligil</a>, <a href="/search/cond-mat?searchtype=author&query=Petrou%2C+A">A. Petrou</a>, <a href="/search/cond-mat?searchtype=author&query=Zutic%2C+I">I. Zutic</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+W">W-C. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Fan%2C+W+C">W. C. Fan</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=McCombe%2C+B+D">B. D. McCombe</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="0912.0138v1-abstract-short" style="display: inline;"> We present evidence of magnetic ordering in type-II (Zn, Mn) Te quantum dots. This ordering is attributed to the formation of bound magnetic polarons caused by the exchange interaction between the strongly localized holes and Mn within the dots. In our photoluminescence studies, the magnetic polarons are detected at temperatures up to ~ 200 K, with a binding energy of ~ 40 meV. In addition, thes… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0912.0138v1-abstract-full').style.display = 'inline'; document.getElementById('0912.0138v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="0912.0138v1-abstract-full" style="display: none;"> We present evidence of magnetic ordering in type-II (Zn, Mn) Te quantum dots. This ordering is attributed to the formation of bound magnetic polarons caused by the exchange interaction between the strongly localized holes and Mn within the dots. In our photoluminescence studies, the magnetic polarons are detected at temperatures up to ~ 200 K, with a binding energy of ~ 40 meV. In addition, these dots display an unusually small Zeeman shift with applied field (2 meV at 10 T). This behavior is explained by a small and weakly temperature-dependent magnetic susceptibility due to anti-ferromagnetic coupling of the Mn spins. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0912.0138v1-abstract-full').style.display = 'none'; document.getElementById('0912.0138v1-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, 2009; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2009. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/0808.1123">arXiv:0808.1123</a> <span> [<a href="https://arxiv.org/pdf/0808.1123">pdf</a>, <a href="https://arxiv.org/format/0808.1123">other</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> </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/PhysRevB.79.165208">10.1103/PhysRevB.79.165208 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ferromagnetism and spin polarized charge carriers in In$_{2}$O$_{3}$ thin films </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Panguluri%2C+R+P">Raghava P. Panguluri</a>, <a href="/search/cond-mat?searchtype=author&query=Kharel%2C+P">P. Kharel</a>, <a href="/search/cond-mat?searchtype=author&query=Sudakar%2C+C">C. Sudakar</a>, <a href="/search/cond-mat?searchtype=author&query=Naik%2C+R">R. Naik</a>, <a href="/search/cond-mat?searchtype=author&query=Suryanarayanan%2C+R">R. Suryanarayanan</a>, <a href="/search/cond-mat?searchtype=author&query=Naik%2C+V+M">V. M. Naik</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Nadgorny%2C+B">B. Nadgorny</a>, <a href="/search/cond-mat?searchtype=author&query=Lawes%2C+G">G. Lawes</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="0808.1123v1-abstract-short" style="display: inline;"> We present evidence for spin polarized charge carriers in In$_2$O$_3$ films. Both In$_2$O$_3$ and Cr doped In$_2$O$_3$ films exhibit room temperature ferromagnetism after vacuum annealing, with a saturation moment of approximately 0.5 emu/cm$^3$. We used Point Contact Andreev Reflection measurements to directly determine the spin polarization, which was found to be approximately 50$\pm$5% for bo… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0808.1123v1-abstract-full').style.display = 'inline'; document.getElementById('0808.1123v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="0808.1123v1-abstract-full" style="display: none;"> We present evidence for spin polarized charge carriers in In$_2$O$_3$ films. Both In$_2$O$_3$ and Cr doped In$_2$O$_3$ films exhibit room temperature ferromagnetism after vacuum annealing, with a saturation moment of approximately 0.5 emu/cm$^3$. We used Point Contact Andreev Reflection measurements to directly determine the spin polarization, which was found to be approximately 50$\pm$5% for both compositions. These results are consistent with suggestions that the ferromagnetism observed in certain oxide semiconductors may be carrier mediated. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0808.1123v1-abstract-full').style.display = 'none'; document.getElementById('0808.1123v1-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, 2008; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2008. </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 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/0807.3928">arXiv:0807.3928</a> <span> [<a href="https://arxiv.org/pdf/0807.3928">pdf</a>, <a href="https://arxiv.org/ps/0807.3928">ps</a>, <a href="https://arxiv.org/format/0807.3928">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</span> </div> </div> <p class="title is-5 mathjax"> Chiral Symmetry and Electron Spin Relaxation of Lithium Donors in Silicon </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Tyryshkin%2C+A+M">A. M. Tyryshkin</a>, <a href="/search/cond-mat?searchtype=author&query=Lyon%2C+S+A">S. A. Lyon</a>, <a href="/search/cond-mat?searchtype=author&query=Schenkel%2C+T">T. Schenkel</a>, <a href="/search/cond-mat?searchtype=author&query=Ager%2C+J+W">J. W. Ager</a>, <a href="/search/cond-mat?searchtype=author&query=Haller%2C+E+E">E. E. Haller</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="0807.3928v1-abstract-short" style="display: inline;"> We report theoretical and experimental studies of the longitudinal electron spin and orbital relaxation time of interstitial Li donors in $^{28}$Si. We predict that despite the near-degeneracy of the ground-state manifold the spin relaxation times are extremely long for the temperatures below 0.3 K. This prediction is based on a new finding of the chiral symmetry of the donor states, which presi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0807.3928v1-abstract-full').style.display = 'inline'; document.getElementById('0807.3928v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="0807.3928v1-abstract-full" style="display: none;"> We report theoretical and experimental studies of the longitudinal electron spin and orbital relaxation time of interstitial Li donors in $^{28}$Si. We predict that despite the near-degeneracy of the ground-state manifold the spin relaxation times are extremely long for the temperatures below 0.3 K. This prediction is based on a new finding of the chiral symmetry of the donor states, which presists in the presence of random strains and magnetic fields parallel to one of the cubic axes. Experimentally observed kinetics of magnetization reversal at 2.1 K and 4.5 K are in a very close agreement with the theory. To explain these kinetics we introduced a new mechanism of spin decoherence based on a combination of a small off-site displacement of the Li atom and an umklapp phonon process. Both these factors weakly break chiral symmetry and enable the long-term spin relaxation. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0807.3928v1-abstract-full').style.display = 'none'; document.getElementById('0807.3928v1-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 July, 2008; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2008. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/0705.4464">arXiv:0705.4464</a> <span> [<a href="https://arxiv.org/pdf/0705.4464">pdf</a>, <a href="https://arxiv.org/ps/0705.4464">ps</a>, <a href="https://arxiv.org/format/0705.4464">other</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="Other Condensed Matter">cond-mat.other</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.99.257202">10.1103/PhysRevLett.99.257202 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Thermodynamics of carrier-mediated magnetism in semiconductors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Zutic%2C+I">Igor Zutic</a>, <a href="/search/cond-mat?searchtype=author&query=Erwin%2C+S+C">Steven C. Erwin</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="0705.4464v1-abstract-short" style="display: inline;"> We propose a model of carrier-mediated ferromagnetism in semiconductors that accounts for the temperature dependence of the carriers. The model permits analysis of the thermodynamic stability of competing magnetic states, opening the door to the construction of magnetic phase diagrams. As an example we analyze the stability of a possible reentrant ferromagnetic semiconductor, in which increasing… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0705.4464v1-abstract-full').style.display = 'inline'; document.getElementById('0705.4464v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="0705.4464v1-abstract-full" style="display: none;"> We propose a model of carrier-mediated ferromagnetism in semiconductors that accounts for the temperature dependence of the carriers. The model permits analysis of the thermodynamic stability of competing magnetic states, opening the door to the construction of magnetic phase diagrams. As an example we analyze the stability of a possible reentrant ferromagnetic semiconductor, in which increasing temperature leads to an increased carrier density, such that the enhanced exchange coupling between magnetic impurities results in the onset of ferromagnetism as temperature is raised. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0705.4464v1-abstract-full').style.display = 'none'; document.getElementById('0705.4464v1-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 May, 2007; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2007. </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, 3 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 99, 257202 (2007) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0702474">arXiv:cond-mat/0702474</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0702474">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0702474">ps</a>, <a href="https://arxiv.org/format/cond-mat/0702474">other</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> </div> </div> <p class="title is-5 mathjax"> Scattering by Atomic Spins and Magnetoresistance in Dilute Magnetic Semiconductors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+M+F+A+G">M. Foygel A. G. Petukhov</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="cond-mat/0702474v1-abstract-short" style="display: inline;"> We studied electrical transport in magnetic semiconductors, which is determined by scattering of free carriers off localized magnetic moments. We calculated the scattering time and the mobility of the majority and minority-spin carriers with both the effects of thermal spin fluctuations and of spatial disorder of magnetic atoms taken into account. These are responsible for the magnetic-field dep… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0702474v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0702474v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0702474v1-abstract-full" style="display: none;"> We studied electrical transport in magnetic semiconductors, which is determined by scattering of free carriers off localized magnetic moments. We calculated the scattering time and the mobility of the majority and minority-spin carriers with both the effects of thermal spin fluctuations and of spatial disorder of magnetic atoms taken into account. These are responsible for the magnetic-field dependence of electrical resistivity. Namely, the application of the external magnetic field suppresses the thermodynamic spin fluctuations thus promoting negative magnetoresistance. Simultaneously, scattering off the built-in spatial fluctuations of the atomic spin concentrations may increase with the magnetic field. The latter effect is due to the growth of the magnitude of random local Zeeman splittings with the magnetic field. It promotes positive magnetoresistance. We discuss the role of the above effects on magnetoresistance of non-degenerate semiconductors where magnetic impurities are electrically active or neutral. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0702474v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0702474v1-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 February, 2007; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2007. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0609599">arXiv:cond-mat/0609599</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0609599">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0609599">ps</a>, <a href="https://arxiv.org/format/cond-mat/0609599">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</span> </div> </div> <p class="title is-5 mathjax"> Complete spin polarization of degenerate electrons in semiconductors near ferromagnetic contacts </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Osipov%2C+V+V">V. V. Osipov</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="cond-mat/0609599v1-abstract-short" style="display: inline;"> We show that spin polarization of electron density in nonmagnetic degenerate semiconductors can achieve 100%. This effect is realized in ferromagnet-semiconductor $FM-n^{+}$-$n$ junctions even at moderate spin selectivity of the $FM-n^{+}$ contact when the electrons are extracted from the heavily doped $n^{+}-$semiconductor into the ferromagnet. We derived a general equation relating spin polari… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0609599v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0609599v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0609599v1-abstract-full" style="display: none;"> We show that spin polarization of electron density in nonmagnetic degenerate semiconductors can achieve 100%. This effect is realized in ferromagnet-semiconductor $FM-n^{+}$-$n$ junctions even at moderate spin selectivity of the $FM-n^{+}$ contact when the electrons are extracted from the heavily doped $n^{+}-$semiconductor into the ferromagnet. We derived a general equation relating spin polarization of the current to that of the electron density in nonmagnetic semiconductors. We found that the effect of the complete spin polarization is achieved near $n^{+}$-$n$ interface when an effective diffusion coefficient goes to zero in this region while the diffusion current remains finite. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0609599v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0609599v1-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 September, 2006; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2006. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0601337">arXiv:cond-mat/0601337</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0601337">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0601337">ps</a>, <a href="https://arxiv.org/format/cond-mat/0601337">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</span> </div> </div> <p class="title is-5 mathjax"> Electronic Control and Readout of Qubit States in Solid State Quantum Computing Systems </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Osipov%2C+V+V">V. V. Osipov</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</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="cond-mat/0601337v2-abstract-short" style="display: inline;"> We demonstrate that an $n^+/i/n^+$ junction is the most suitable candidate for electronic control and readout of qubit states in quantum computing systems based on shallow impurities. The signature of this system is that the $n^+-$regions serve as metallic electrodes separated form the $i-$region by a self-induced barrier (internal workfunction). The $n^+/i/n^+$ system mimics the properties of a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0601337v2-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0601337v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0601337v2-abstract-full" style="display: none;"> We demonstrate that an $n^+/i/n^+$ junction is the most suitable candidate for electronic control and readout of qubit states in quantum computing systems based on shallow impurities. The signature of this system is that the $n^+-$regions serve as metallic electrodes separated form the $i-$region by a self-induced barrier (internal workfunction). The $n^+/i/n^+$ system mimics the properties of a metal-vacuum-metal junction with the qubit (impurity atom) placed in a ``vacuum'' $i$-region between two ``metallic'' $n^+$ electrodes. We will show that the self-induced barrier exists in a sufficiently wide range of the concentration of dopants in the $n^+$-semiconductor (e.g. up to $10^{21}$ cm$^{-3}$ for Si) and its height can be controlled by tuning the doping level. A shallow donor placed in a vacuum $i$-region will be populated with one electron in equilibrium. In the case of Li donor in Si the $n^+$-electrodes will be used for a precision placement of the Li atom during the growth process; for voltage control and manipulation of the qubit states; and for a qubit readout by means of the optically stimulated resonant tunnelling. Another important feature of our system is that the qubit states (first two lowest energy levels of Li in Si) are separated by an energy gap from a continuum of the many-body states of the controlling electrodes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0601337v2-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0601337v2-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 January, 2006; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 16 January, 2006; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2006. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0506670">arXiv:cond-mat/0506670</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0506670">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0506670">ps</a>, <a href="https://arxiv.org/format/cond-mat/0506670">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</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/10.1063/1.2128060">10.1063/1.2128060 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Complete spin polarization of electrons in semiconductor layers and quantum dots </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Osipov%2C+V+V">V. V. Osipov</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</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="cond-mat/0506670v1-abstract-short" style="display: inline;"> We demonstrate that non-equilibrium electrons in thin nonmagnetic semiconductor layers or quantum dots can be fully spin polarized by means of simultaneous electrical spin injection and extraction. The complete spin polarization is achieved if the thin layers or quantum dots are placed between two ferromagnetic metal contacts with moderate spin injection coefficients and antiparallel magnetizati… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0506670v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0506670v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0506670v1-abstract-full" style="display: none;"> We demonstrate that non-equilibrium electrons in thin nonmagnetic semiconductor layers or quantum dots can be fully spin polarized by means of simultaneous electrical spin injection and extraction. The complete spin polarization is achieved if the thin layers or quantum dots are placed between two ferromagnetic metal contacts with moderate spin injection coefficients and antiparallel magnetizations. The sign of the spin polarization is determined by the direction of the current. Aplications of this effect in spintronics and quantum information processing are discussed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0506670v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0506670v1-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 June, 2005; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2005. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0506625">arXiv:cond-mat/0506625</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0506625">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0506625">ps</a>, <a href="https://arxiv.org/format/cond-mat/0506625">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</span> </div> </div> <p class="title is-5 mathjax"> Complete spin extraction from semiconductors near ferromagnet-semiconductor interfaces </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Osipov%2C+V+V">V. V. Osipov</a>, <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="cond-mat/0506625v1-abstract-short" style="display: inline;"> We show that spin polarization of electrons in nonmagnetic semiconductors near specially tailored ferromagnet-semiconductor junctions can achieve 100%. This effect is realized even at moderate spin injection coefficients of the contact when these coefficients only weakly depend on the current. The effect of complete spin extraction occurs at relatively strong electric fields and arises from a re… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0506625v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0506625v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0506625v1-abstract-full" style="display: none;"> We show that spin polarization of electrons in nonmagnetic semiconductors near specially tailored ferromagnet-semiconductor junctions can achieve 100%. This effect is realized even at moderate spin injection coefficients of the contact when these coefficients only weakly depend on the current. The effect of complete spin extraction occurs at relatively strong electric fields and arises from a reduction of spin penetration length due to the drift of electrons from a semiconductor towards the spin-selective tunnel junction. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0506625v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0506625v1-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 June, 2005; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2005. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/quant-ph/0407220">arXiv:quant-ph/0407220</a> <span> [<a href="https://arxiv.org/pdf/quant-ph/0407220">pdf</a>, <a href="https://arxiv.org/ps/quant-ph/0407220">ps</a>, <a href="https://arxiv.org/format/quant-ph/0407220">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</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/PhysRevB.72.081304">10.1103/PhysRevB.72.081304 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Quantum computing on long-lived donor states of Li in Si </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Smelyanskiy%2C+V+N">V. N. Smelyanskiy</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Osipov%2C+V+V">V. V. Osipov</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="quant-ph/0407220v3-abstract-short" style="display: inline;"> We predict a gigantically long lifetime of the first excited state of an interstitial lithium donor in silicon. The nature of this effect roots in the anomalous level structure of the {\em 1s} Li manifold under external stress. Namely, the coupling between the lowest two states of the opposite parity is very weak and occurs via intervalley phonon transitions only. We propose to use these states… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('quant-ph/0407220v3-abstract-full').style.display = 'inline'; document.getElementById('quant-ph/0407220v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="quant-ph/0407220v3-abstract-full" style="display: none;"> We predict a gigantically long lifetime of the first excited state of an interstitial lithium donor in silicon. The nature of this effect roots in the anomalous level structure of the {\em 1s} Li manifold under external stress. Namely, the coupling between the lowest two states of the opposite parity is very weak and occurs via intervalley phonon transitions only. We propose to use these states under the controlled ac and dc stress to process quantum information. We find an unusual form of the elastic-dipole interaction between %the electronic transitions in different donors. This interaction scales with the inter-donor distance $R$ as $R^{-3}$ or $R^{-5}$ for the transitions between the states of the same or opposite parity, respectively. The long-range $R^{-3}$ interaction provides a high fidelity mechanism for 2-qubit operations. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('quant-ph/0407220v3-abstract-full').style.display = 'none'; document.getElementById('quant-ph/0407220v3-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 November, 2004; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 27 July, 2004; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2004. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0211301">arXiv:cond-mat/0211301</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0211301">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0211301">ps</a>, <a href="https://arxiv.org/format/cond-mat/0211301">other</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> </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/PhysRevB.67.134205">10.1103/PhysRevB.67.134205 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Variable-Range Hopping of Spin Polarons: Magnetoresistance in a Modified Mott Regime </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Foygel%2C+M">M. Foygel</a>, <a href="/search/cond-mat?searchtype=author&query=Morris%2C+R+D">R. D. Morris</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="cond-mat/0211301v1-abstract-short" style="display: inline;"> We analize electrical conductivity controlled by hopping of bound spin polarons in disordered solids with wide distributions of electron energies and polaron shifts (barriers). By means of percolation theory and Monte Carlo simulations we have shown that in such materials at low temperatures, when hopping occurs in the vicinity of the Fermi level, a hard polaron gap does not manifest itself in t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0211301v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0211301v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0211301v1-abstract-full" style="display: none;"> We analize electrical conductivity controlled by hopping of bound spin polarons in disordered solids with wide distributions of electron energies and polaron shifts (barriers). By means of percolation theory and Monte Carlo simulations we have shown that in such materials at low temperatures, when hopping occurs in the vicinity of the Fermi level, a hard polaron gap does not manifest itself in the transport properties. This happens because as temperature decreases the hopping polaron trades the decreasing electron and polaron barriers for increasing hopping distance. As a result, in the absence of the Coulomb correlation effects, in this variable-range variable-barrier hopping regime, the electrical resistivity as a function of temperature obeys a non-activation law, which differs from the standard Mott law. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0211301v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0211301v1-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> 14 November, 2002; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2002. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0211300">arXiv:cond-mat/0211300</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0211300">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0211300">ps</a>, <a href="https://arxiv.org/format/cond-mat/0211300">other</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> </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/PhysRevB.68.125332">10.1103/PhysRevB.68.125332 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Electron Spin Polarization in Resonant Interband Tunneling Devices </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Demchenko%2C+D+O">D. O. Demchenko</a>, <a href="/search/cond-mat?searchtype=author&query=Chantis%2C+A+N">A. N. Chantis</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="cond-mat/0211300v1-abstract-short" style="display: inline;"> We study spin-dependent interband resonant tunneling in double-barrier InAs/AlSb/ GaMnSb heterostructures. We demonstrate that these structures can be used as spin filters utilizing spin-selective tunneling of electrons through the light-hole resonant channel. High densities of the spin polarized electrons injected into bulk InAs make spin resonant tunneling devices a viable alternative for inje… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0211300v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0211300v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0211300v1-abstract-full" style="display: none;"> We study spin-dependent interband resonant tunneling in double-barrier InAs/AlSb/ GaMnSb heterostructures. We demonstrate that these structures can be used as spin filters utilizing spin-selective tunneling of electrons through the light-hole resonant channel. High densities of the spin polarized electrons injected into bulk InAs make spin resonant tunneling devices a viable alternative for injecting spins into a semiconductor. Another striking feature of the proposed devices is the possibility of inducing additional resonant channels corresponding to the heavy holes. This can be implemented by saturating the in-plane magnetization in the quantum well. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0211300v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0211300v1-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> 14 November, 2002; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2002. </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 eps 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/cond-mat/0209329">arXiv:cond-mat/0209329</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0209329">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0209329">ps</a>, <a href="https://arxiv.org/format/cond-mat/0209329">other</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> </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.89.227201">10.1103/PhysRevLett.89.227201 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Self-compensation in manganese-doped ferromagnetic semiconductors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Erwin%2C+S+C">Steven C. Erwin</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</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="cond-mat/0209329v1-abstract-short" style="display: inline;"> We present a theory of interstitial Mn in Mn-doped ferromagnetic semiconductors. Using density-functional theory, we show that under the non-equilibrium conditions of growth, interstitial Mn is easily formed near the surface by a simple low-energy adsorption pathway. In GaAs, isolated interstitial Mn is an electron donor, each compensating two substitutional Mn acceptors. Within an impurity-band… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0209329v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0209329v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0209329v1-abstract-full" style="display: none;"> We present a theory of interstitial Mn in Mn-doped ferromagnetic semiconductors. Using density-functional theory, we show that under the non-equilibrium conditions of growth, interstitial Mn is easily formed near the surface by a simple low-energy adsorption pathway. In GaAs, isolated interstitial Mn is an electron donor, each compensating two substitutional Mn acceptors. Within an impurity-band model, partial compensation promotes ferromagnetic order below the metal-insulator transition, with the highest Curie temperature occurring for 0.5 holes per substitutional Mn. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0209329v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0209329v1-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> 13 September, 2002; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2002. </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, 3 figures, to appear in Phys. Rev. Lett</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 89, 227201 (2002) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0206548">arXiv:cond-mat/0206548</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0206548">pdf</a>, <a href="https://arxiv.org/ps/cond-mat/0206548">ps</a>, <a href="https://arxiv.org/format/cond-mat/0206548">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</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/10.1103/PhysRevB.67.153106">10.1103/PhysRevB.67.153106 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Correlated metals and the LDA+U method </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Mazin%2C+I+I">I. I. Mazin</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Chioncel%2C+L">L. Chioncel</a>, <a href="/search/cond-mat?searchtype=author&query=Lichtenstein%2C+A+I">A. I. Lichtenstein</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="cond-mat/0206548v2-abstract-short" style="display: inline;"> While LDA+U method is well established for strongly correlated materials with well localized orbitals, its application to weakly correlated metals is questionable. By extending the LDA Stoner approach onto LDA+U, we show that LDA+U enhances the Stoner factor, while reducing the density of states. Arguably the most important correlation effects in metals, fluctuation-induced mass renormalization… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0206548v2-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0206548v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0206548v2-abstract-full" style="display: none;"> While LDA+U method is well established for strongly correlated materials with well localized orbitals, its application to weakly correlated metals is questionable. By extending the LDA Stoner approach onto LDA+U, we show that LDA+U enhances the Stoner factor, while reducing the density of states. Arguably the most important correlation effects in metals, fluctuation-induced mass renormalization and suppression of the Stoner factor, are missing from LDA+U. On the other hand, for {\it moderately} correlated metals LDA+U may be useful. With this in mind, we derive a new version of LDA+U that is consistent with the Hohenberg-Kohn theorem and can be formulated as a constrained density functional theory. We illustrate all of the above on concrete examples, including the controversial case of magnetism in FeAl. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0206548v2-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0206548v2-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, 2002; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 27 June, 2002; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2002. </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">Substantial changes. In particular, examples of application of the proposed functional are added</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B, 67, 153106 (2003) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/cond-mat/0110570">arXiv:cond-mat/0110570</a> <span> [<a href="https://arxiv.org/pdf/cond-mat/0110570">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> </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.89.166602">10.1103/PhysRevLett.89.166602 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Reduction Of Spin Injection Efficiency by Interface Spin Scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Stroud%2C+R+M">R. M. Stroud</a>, <a href="/search/cond-mat?searchtype=author&query=Hanbicki%2C+A+T">A. T. Hanbicki</a>, <a href="/search/cond-mat?searchtype=author&query=Park%2C+Y+D">Y. D. Park</a>, <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Jonker%2C+B+T">B. T. Jonker</a>, <a href="/search/cond-mat?searchtype=author&query=Itskos%2C+G">G. Itskos</a>, <a href="/search/cond-mat?searchtype=author&query=Kioseoglou%2C+G">G. Kioseoglou</a>, <a href="/search/cond-mat?searchtype=author&query=Furis%2C+M">M. Furis</a>, <a href="/search/cond-mat?searchtype=author&query=Petrou%2C+A">A. Petrou</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="cond-mat/0110570v1-abstract-short" style="display: inline;"> We report the first experimental demonstration that interface microstructure limits diffusive electrical spin injection efficiency across heteroepitaxial interfaces. A theoretical treatment shows that the suppression of spin injection due to interface defects follows directly from the contribution of the defect potential to the spin-orbit interaction, resulting in enhanced spin-flip scattering.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0110570v1-abstract-full').style.display = 'inline'; document.getElementById('cond-mat/0110570v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="cond-mat/0110570v1-abstract-full" style="display: none;"> We report the first experimental demonstration that interface microstructure limits diffusive electrical spin injection efficiency across heteroepitaxial interfaces. A theoretical treatment shows that the suppression of spin injection due to interface defects follows directly from the contribution of the defect potential to the spin-orbit interaction, resulting in enhanced spin-flip scattering. An inverse correlation between spin-polarized electron injection efficiency and interface defect density is demonstrated for ZnMnSe/AlGaAs-GaAs spin-LEDs with spin injection efficiencies of 0 to 85%. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('cond-mat/0110570v1-abstract-full').style.display = 'none'; document.getElementById('cond-mat/0110570v1-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> 26 October, 2001; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2001. </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">13 pages, 5 figures; submitted to PRL</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 89, 166602 (2002) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/mtrl-th/9508003">arXiv:mtrl-th/9508003</a> <span> [<a href="https://arxiv.org/pdf/mtrl-th/9508003">pdf</a>, <a href="https://arxiv.org/ps/mtrl-th/9508003">ps</a>, <a href="https://arxiv.org/format/mtrl-th/9508003">other</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> </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/PhysRevB.53.3646">10.1103/PhysRevB.53.3646 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Spin-dependent resonant tunneling through semimetallic ErAs quantum wells </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Petukhov%2C+A+G">A. G. Petukhov</a>, <a href="/search/cond-mat?searchtype=author&query=Lambrecht%2C+W+R+L">W. R. L. Lambrecht</a>, <a href="/search/cond-mat?searchtype=author&query=Segall%2C+B">B. Segall</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="mtrl-th/9508003v1-abstract-short" style="display: inline;"> Resonant tunneling through semimetallic ErAs quantum wells embedded in GaAs structures with AlAs barriers was recently found to exhibit an intriguing behavior in magnetic fields which is explained in terms of tunneling selection rules and the spin-polarized band structure including spin-orbit coupling. </span> <span class="abstract-full has-text-grey-dark mathjax" id="mtrl-th/9508003v1-abstract-full" style="display: none;"> Resonant tunneling through semimetallic ErAs quantum wells embedded in GaAs structures with AlAs barriers was recently found to exhibit an intriguing behavior in magnetic fields which is explained in terms of tunneling selection rules and the spin-polarized band structure including spin-orbit coupling. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('mtrl-th/9508003v1-abstract-full').style.display = 'none'; document.getElementById('mtrl-th/9508003v1-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 August, 1995; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 1995. </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, figures supplied as self-unpacking figures.uu, uses epsfig.sty to incorporate figures in preprint</span> </p> </li> </ol> <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" 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