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</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/2502.01258">arXiv:2502.01258</a> <span> [<a href="https://arxiv.org/pdf/2502.01258">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Computational Physics">physics.comp-ph</span> </div> </div> <p class="title is-5 mathjax"> Polarizing altermagnets by ultrafast asymmetric spin dynamics </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zhou%2C+Z">Zhaobo Zhou</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">Sangeeta Sharma</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">John Kay Dewhurst</a>, <a href="/search/physics?searchtype=author&query=He%2C+J">Junjie He</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="2502.01258v1-abstract-short" style="display: inline;"> Laser pulses are known to induce symmetric demagnetization; equal loss of magnetic moments in the identical sublattices of antiferromagnets and ferromagnets at ultrashort timescale. This is due to their identical local electronic structures guided by the underlying symmetries. Using time-dependent density functional theory, we demonstrate that laser pulses can drive asymmetric demagnetization dyna… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.01258v1-abstract-full').style.display = 'inline'; document.getElementById('2502.01258v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2502.01258v1-abstract-full" style="display: none;"> Laser pulses are known to induce symmetric demagnetization; equal loss of magnetic moments in the identical sublattices of antiferromagnets and ferromagnets at ultrashort timescale. This is due to their identical local electronic structures guided by the underlying symmetries. Using time-dependent density functional theory, we demonstrate that laser pulses can drive asymmetric demagnetization dynamics of identical sublattices in the d-wave altermagnet RuO2, resulting in a photo-induced ferrimagnetic state with a net moment of ~0.2 渭B per unit cell. This polarization arises from the momentum-dependent spin splitting, which is unique to altermagnets, and which induces a momentum-dependent optical intersite spin transfer effect. Furthermore, the ferrimagnetic polarization is highly controllable; depends on the direction of the linear polarized laser. The excitation along the spin-polarized planes breaks the symmetry of the momentum-space magnetization distribution, leading to inequivalent spin-resolved charge transfer between sublattices across both momentum and real space. These findings uncover novel laser-driven pathways to control magnetic order in altermagnets, enabling a phase transition from AM to ferri-magnetic state. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.01258v1-abstract-full').style.display = 'none'; document.getElementById('2502.01258v1-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 February, 2025; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2025. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2405.12690">arXiv:2405.12690</a> <span> [<a href="https://arxiv.org/pdf/2405.12690">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> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Light induced magnetic order </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Jauk%2C+T">T. Jauk</a>, <a href="/search/physics?searchtype=author&query=Hampel%2C+H">H. Hampel</a>, <a href="/search/physics?searchtype=author&query=Walowski%2C+J">J. Walowski</a>, <a href="/search/physics?searchtype=author&query=Komatsu%2C+K">K. Komatsu</a>, <a href="/search/physics?searchtype=author&query=Kredl%2C+J">J. Kredl</a>, <a href="/search/physics?searchtype=author&query=Harris-Lee%2C+E+I">E. I. Harris-Lee</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=M%C3%BCnzenberg%2C+M">M. M眉nzenberg</a>, <a href="/search/physics?searchtype=author&query=Shallcross%2C+S">S. Shallcross</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">S. Sharma</a>, <a href="/search/physics?searchtype=author&query=Schultze%2C+M">M. Schultze</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2405.12690v1-abstract-short" style="display: inline;"> Heat and disorder are opponents of magnetism. This fact, expressed in Curie's law established more than a century ago, holds even in the highly non-equilibrium interaction of ultra-intense laser pulses with magnetic matter. In contradiction to this, here we demonstrate that optical excitation of a ferromagnet can abrogate the link between temperature and order and observe 100 femtosecond class las… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.12690v1-abstract-full').style.display = 'inline'; document.getElementById('2405.12690v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2405.12690v1-abstract-full" style="display: none;"> Heat and disorder are opponents of magnetism. This fact, expressed in Curie's law established more than a century ago, holds even in the highly non-equilibrium interaction of ultra-intense laser pulses with magnetic matter. In contradiction to this, here we demonstrate that optical excitation of a ferromagnet can abrogate the link between temperature and order and observe 100 femtosecond class laser pulses to drive a reduction in spin entropy, concomitant to an increase in spin polarization and magnetic moment persisting after relaxation back to local charge equilibrium. This both establishes disorder as an unexpected resource for magnetic control at ultrafast times and, by the provision of a purely electronic mechanism that does not involve reconfiguration of the crystal lattice, suggests a novel scheme for spin-based signal processing and information storage significantly faster than current methodology. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.12690v1-abstract-full').style.display = 'none'; document.getElementById('2405.12690v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 21 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2207.11461">arXiv:2207.11461</a> <span> [<a href="https://arxiv.org/pdf/2207.11461">pdf</a>, <a href="https://arxiv.org/format/2207.11461">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="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.106.L060302">10.1103/PhysRevB.106.L060302 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Electronic origin of x-ray absorption peak shifts </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Shallcross%2C+S">S. Shallcross</a>, <a href="/search/physics?searchtype=author&query=Schmising%2C+C+v+K">C. v. Korff Schmising</a>, <a href="/search/physics?searchtype=author&query=Elliott%2C+P">P. Elliott</a>, <a href="/search/physics?searchtype=author&query=Eisebitt%2C+S">S. Eisebitt</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">S. Sharma</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="2207.11461v1-abstract-short" style="display: inline;"> Encoded in the transient x-ray absorption (XAS) and magnetic circular (MCD) response functions resides a wealth of information of the microscopic processes of ultrafast demagnetisation. Employing state of the art first principles dynamical simulations we show that the experimentally observed energy shift of the L3 XAS peak in Ni, and the absence of a corresponding shift in the dichroic MCD respons… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2207.11461v1-abstract-full').style.display = 'inline'; document.getElementById('2207.11461v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2207.11461v1-abstract-full" style="display: none;"> Encoded in the transient x-ray absorption (XAS) and magnetic circular (MCD) response functions resides a wealth of information of the microscopic processes of ultrafast demagnetisation. Employing state of the art first principles dynamical simulations we show that the experimentally observed energy shift of the L3 XAS peak in Ni, and the absence of a corresponding shift in the dichroic MCD response, can be explained in terms of laser induced changes in band occupation. Strikingly, we predict that for the same ultrashort pump pulse applied to Co the opposite effect will occur: a substantial shift upwards in energy of the MCD peaks will be accompanied by very small change in the position of XAS peaks, a fact we relate to the reduced $d$-band filling of Co that allows a greater energetic range above the Fermi energy into which charge can be excited. We also carefully elucidate the dependence of this effect on pump pulse parameters. These findings (i) establish a electronic origin for early time peak shifts in transient XAS and MCD spectroscopy and (ii) illustrate the rich information that may be extracted from transient response functions of the underlying dynamical system. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2207.11461v1-abstract-full').style.display = 'none'; document.getElementById('2207.11461v1-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 July, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">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/2012.03247">arXiv:2012.03247</a> <span> [<a href="https://arxiv.org/pdf/2012.03247">pdf</a>, <a href="https://arxiv.org/format/2012.03247">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1063/5.0076198">10.1063/5.0076198 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ultrafast optical control over spin and momentum in solids </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Li%2C+Q+Z">Q. Z. Li</a>, <a href="/search/physics?searchtype=author&query=Shallcross%2C+S">S. Shallcross</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">S. Sharma</a>, <a href="/search/physics?searchtype=author&query=Elliott%2C+P">P. Elliott</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="2012.03247v1-abstract-short" style="display: inline;"> The coupling of laser light to matter can exert sub-cycle coherent control over material properties, with optically induced currents and magnetism shown to be controllable on ultrafast femtosecond time scales. Here, by employing laser light consisting of both linear and circular pulses, we show that charge of specified spin and crystal momentum can be created with precision throughout the first Br… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2012.03247v1-abstract-full').style.display = 'inline'; document.getElementById('2012.03247v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2012.03247v1-abstract-full" style="display: none;"> The coupling of laser light to matter can exert sub-cycle coherent control over material properties, with optically induced currents and magnetism shown to be controllable on ultrafast femtosecond time scales. Here, by employing laser light consisting of both linear and circular pulses, we show that charge of specified spin and crystal momentum can be created with precision throughout the first Brillouin zone. Our hybrid pulses induce in a controlled way both adiabatic intraband motion as well as vertical interband excitation between valence and conduction bands, and require only a gapped spin split valley structure for their implementation. This scenario is commonly found in the 2d semi-conductors, and we demonstrate our approach with monolayer WSe$_2$. We thus establish a route from laser light to local control over excitations in reciprocal space, opening the way to the preparation of momenta specified excited states at ultrafast time scales. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2012.03247v1-abstract-full').style.display = 'none'; document.getElementById('2012.03247v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 December, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2020. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2005.02872">arXiv:2005.02872</a> <span> [<a href="https://arxiv.org/pdf/2005.02872">pdf</a>, <a href="https://arxiv.org/format/2005.02872">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <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/PhysRevB.102.100405">10.1103/PhysRevB.102.100405 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Distinct Ultrafast Electronic and Magnetic Response in M-edge Magnetic Circular Dichroism </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Yao%2C+K">Kelvin Yao</a>, <a href="/search/physics?searchtype=author&query=Willems%2C+F">Felix Willems</a>, <a href="/search/physics?searchtype=author&query=Schmising%2C+C+v+K">Clemens von Korff Schmising</a>, <a href="/search/physics?searchtype=author&query=Radu%2C+I">Ilie Radu</a>, <a href="/search/physics?searchtype=author&query=Strueber%2C+C">Christian Strueber</a>, <a href="/search/physics?searchtype=author&query=Schick%2C+D">Daniel Schick</a>, <a href="/search/physics?searchtype=author&query=Engel%2C+D">Dieter Engel</a>, <a href="/search/physics?searchtype=author&query=Tsukamoto%2C+A">Arata Tsukamoto</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">Sangeeta Sharma</a>, <a href="/search/physics?searchtype=author&query=Eisebitt%2C+S">Stefan Eisebitt</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2005.02872v1-abstract-short" style="display: inline;"> Experimental investigations of ultrafast magnetization dynamics increasingly employ resonant magnetic spectroscopy in the ultraviolet spectral range. Besides allowing to disentangle the element-specific transient response of functional magnetic systems, these techniques also promise to access attosecond to few-femtosecond dynamics of spin excitations. Here, we report on a systematic study of trans… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.02872v1-abstract-full').style.display = 'inline'; document.getElementById('2005.02872v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2005.02872v1-abstract-full" style="display: none;"> Experimental investigations of ultrafast magnetization dynamics increasingly employ resonant magnetic spectroscopy in the ultraviolet spectral range. Besides allowing to disentangle the element-specific transient response of functional magnetic systems, these techniques also promise to access attosecond to few-femtosecond dynamics of spin excitations. Here, we report on a systematic study of transient magnetic circular dichroism (MCD) on the transition metals Fe, Co and Ni as well as on a FeNi and GdFe alloy and reveal a delayed onset between the electronic and magnetic response. Supported by \textit{ab-initio} calculations, we attribute our observation to a transient energy shift of the absorption and MCD spectra at the corresponding elemental resonances due to non-equilibrium changes of electron occupations. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.02872v1-abstract-full').style.display = 'none'; document.getElementById('2005.02872v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">8 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 102, 100405 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1812.07420">arXiv:1812.07420</a> <span> [<a href="https://arxiv.org/pdf/1812.07420">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey 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="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41586-019-1333-x">10.1038/s41586-019-1333-x <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Petahertz Spintronics </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Siegrist%2C+F">Florian Siegrist</a>, <a href="/search/physics?searchtype=author&query=Gessner%2C+J+A">Julia A. Gessner</a>, <a href="/search/physics?searchtype=author&query=Ossiander%2C+M">Marcus Ossiander</a>, <a href="/search/physics?searchtype=author&query=Denker%2C+C">Christian Denker</a>, <a href="/search/physics?searchtype=author&query=Chang%2C+Y">Yi-Ping Chang</a>, <a href="/search/physics?searchtype=author&query=Schroeder%2C+M+C">Malte C. Schroeder</a>, <a href="/search/physics?searchtype=author&query=Guggenmos%2C+A">Alexander Guggenmos</a>, <a href="/search/physics?searchtype=author&query=Cui%2C+Y">Yang Cui</a>, <a href="/search/physics?searchtype=author&query=Walowski%2C+J">Jakob Walowski</a>, <a href="/search/physics?searchtype=author&query=Martens%2C+U">Ulrike Martens</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=Kleineberg%2C+U">Ulf Kleineberg</a>, <a href="/search/physics?searchtype=author&query=Muenzenberg%2C+M">Markus Muenzenberg</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">Sangeeta Sharma</a>, <a href="/search/physics?searchtype=author&query=Schultze%2C+M">Martin Schultze</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="1812.07420v1-abstract-short" style="display: inline;"> The enigmatic coupling between electronic and magnetic phenomena was one of the riddles propelling the development of modern electromagnetism. Today, the fully controlled electric field evolution of ultrashort laser pulses permits the direct and ultrafast control of electronic properties of matter and is the cornerstone of light-wave electronics. In sharp contrast, because there is no first order… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1812.07420v1-abstract-full').style.display = 'inline'; document.getElementById('1812.07420v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1812.07420v1-abstract-full" style="display: none;"> The enigmatic coupling between electronic and magnetic phenomena was one of the riddles propelling the development of modern electromagnetism. Today, the fully controlled electric field evolution of ultrashort laser pulses permits the direct and ultrafast control of electronic properties of matter and is the cornerstone of light-wave electronics. In sharp contrast, because there is no first order interaction between light and spins, the magnetic properties of matter can only be affected indirectly on the much slower tens-of-femtosecond timescale in a sequence of optical excitation followed by the rearrangement of the spin structure. Here we record an orders of magnitude faster magnetic switching with sub-femtosecond response time by initiating optical excitations with near-single-cycle laser pulses in a ferromagnetic layer stack. The unfolding dynamics are tracked in real-time by a novel attosecond time-resolved magnetic circular dichroism (atto-MCD) detection scheme revealing optically induced spin and orbital momentum transfer (OISTR) in synchrony with light field driven charge relocation. In tandem with ab-initio quantum dynamical modelling, we show how this mechanism provides simultaneous control over electronic and magnetic properties that are at the heart of spintronic functionality. This first incarnation of attomagnetism observes light field coherent control of spin-dynamics in the initial non-dissipative temporal regime and paves the way towards coherent spintronic applications with Petahertz clock rates. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1812.07420v1-abstract-full').style.display = 'none'; document.getElementById('1812.07420v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 December, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">12 pages, 3+1 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/1412.0996">arXiv:1412.0996</a> <span> [<a href="https://arxiv.org/pdf/1412.0996">pdf</a>, <a href="https://arxiv.org/format/1412.0996">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Computational Physics">physics.comp-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Chemical Physics">physics.chem-ph</span> </div> </div> <p class="title is-5 mathjax"> An efficient algorithm for time propagation within time-dependent density functional theory </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=Krieger%2C+K">K. Krieger</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">S. Sharma</a>, <a href="/search/physics?searchtype=author&query=Gross%2C+E+K+U">E. K. U. Gross</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="1412.0996v1-abstract-short" style="display: inline;"> An efficient algorithm for time propagation of the time-dependent Kohn-Sham equations is presented. The algorithm is based on dividing the Hamiltonian into small time steps and assuming that it is constant over these steps. This allows for the time-propagating Kohn-Sham wave function to be expanded in the instantaneous eigenstates of the Hamiltonian. The stability and efficiency of the algorithm a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1412.0996v1-abstract-full').style.display = 'inline'; document.getElementById('1412.0996v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1412.0996v1-abstract-full" style="display: none;"> An efficient algorithm for time propagation of the time-dependent Kohn-Sham equations is presented. The algorithm is based on dividing the Hamiltonian into small time steps and assuming that it is constant over these steps. This allows for the time-propagating Kohn-Sham wave function to be expanded in the instantaneous eigenstates of the Hamiltonian. The stability and efficiency of the algorithm are tested not just for non-magnetic but also for fully non-collinear magnetic systems. We show that even for delicate properties, like magnetization density, large time-step sizes can be used indicating the stability and efficiency of the algorithm. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1412.0996v1-abstract-full').style.display = 'none'; document.getElementById('1412.0996v1-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 December, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">4 figs</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1201.6237">arXiv:1201.6237</a> <span> [<a href="https://arxiv.org/pdf/1201.6237">pdf</a>, <a href="https://arxiv.org/ps/1201.6237">ps</a>, <a href="https://arxiv.org/format/1201.6237">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Chemical Physics">physics.chem-ph</span> </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/PhysRevA.85.032504">10.1103/PhysRevA.85.032504 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ionization potentials and electron affinities from reduced density matrix functional theory </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/physics?searchtype=author&query=Zarkadoula%2C+E+N">E. N. Zarkadoula</a>, <a href="/search/physics?searchtype=author&query=Sharma%2C+S">S. Sharma</a>, <a href="/search/physics?searchtype=author&query=Dewhurst%2C+J+K">J. K. Dewhurst</a>, <a href="/search/physics?searchtype=author&query=Gross%2C+E+K+U">E. K. U. Gross</a>, <a href="/search/physics?searchtype=author&query=Lathiotakis%2C+N+N">N. N. Lathiotakis</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="1201.6237v2-abstract-short" style="display: inline;"> In the recent work of S. Sharma \emph{et al.}, (arxiv.org: arxiv:0912.1118), a single-electron spectrum associated with the natural orbitals was defined as the derivative of the total energy with respect to the occupation numbers at half filling for the orbital of interest. This idea reproduces the bands of various periodic systems using the appropriate functional quite accurately. In the present… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1201.6237v2-abstract-full').style.display = 'inline'; document.getElementById('1201.6237v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1201.6237v2-abstract-full" style="display: none;"> In the recent work of S. Sharma \emph{et al.}, (arxiv.org: arxiv:0912.1118), a single-electron spectrum associated with the natural orbitals was defined as the derivative of the total energy with respect to the occupation numbers at half filling for the orbital of interest. This idea reproduces the bands of various periodic systems using the appropriate functional quite accurately. In the present work we apply this approximation to the calculation of the ionization potentials and electron affinities of molecular systems using various functionals within the reduced density-matrix functional theory. We demonstrate that this approximation is very successful in general and in particular for certain functionals it performs better than the direct determination of the ionization potentials and electron affinities through the calculation of positive and negative ions respectively. The reason for this is identified to be the inaccuracy that arises from different handling of the open- and closed-shell systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1201.6237v2-abstract-full').style.display = 'none'; document.getElementById('1201.6237v2-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 March, 2012; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 30 January, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2012. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review A, 85, 032504 (2012) </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 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