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  1. Chirality, or handedness, is a geometrical property denoting a lack of mirror symmetry. Chirality is ubiquitous in nature and is associated with the nonreciprocal interactions observed in complex systems ranging from biomolecules to topological materials. Here, we demonstrate that chiral arrangements of dipole-coupled atoms or molecules can facilitate the helicity-dependent superradiant emission of light. We show that the collective modes of these systems experience an emergent spin-orbit coupling that leads to chirality-dependent photon transport and nontrivial topological properties. These phenomena are fully described within the electric dipole approximation, resulting in very strong optical responses. Our results demonstrate an intimate connection between chirality, superradiance, and photon helicity and provide a comprehensive framework for studying electron transport dynamics in chiral molecules using cold atom quantum simulators.

    <supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available May 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10515582-breakdown-steady-state-superradiance-extended-driven-atomic-arrays" itemprop="url"> <span class='span-link' itemprop="name">Breakdown of steady-state superradiance in extended driven atomic arrays</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevResearch.6.023206" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevResearch.6.023206  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Rubies-Bigorda, Oriol</span> <span class="sep">; </span><span class="author" itemprop="author">Zhang, Victoria</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne F</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-05-01">May 2024</time> , Physical Review Research) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>Recent advances in generating well controlled dense arrangements of individual atoms in free space have generated interest in understanding how the extended nature of these systems influences superradiance phenomena. Here, we provide an in-depth analysis on how space-dependent light shifts and decay rates induced by dipole-dipole interactions modify the steady-state properties of coherently driven arrays of quantum emitters. We characterize the steady-state phase diagram, with particular focus on the radiative properties in the steady state. Interestingly, we find that diverging from the well-established Dicke paradigm of equal all-to-all interactions significantly modifies the emission properties. In particular, the prominent quadratic scaling of the radiated light intensity with particle number in the steady state—a hallmark of steady-state Dicke superradiance—is entirely suppressed, resulting in only linear scaling with particle number. We show that this breakdown of steady-state superradiance occurs due to the emergence of additional dissipation channels that populate not only superradiant states but also subradiant ones. The additional contribution of subradiant dark states in the dynamics leads to a divergence in the time scales needed to achieve steady states. Building on this, we further show that measurements taken at finite times for extended atom ensembles reveal properties closely mirroring the idealized Dicke scenario.</p> <sec><supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available May 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10501986-chirality-induced-emergent-spin-orbit-coupling-topological-atomic-lattices" itemprop="url"> <span class='span-link' itemprop="name">Chirality-induced emergent spin-orbit coupling in topological atomic lattices</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevA.109.043525" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevA.109.043525  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Peter, Jonah_S</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne_F</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-04-23">April 2024</time> , Physical Review A) </span> </div> <div class="actions" style="padding-left:10px;"> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10550990-modifying-cooperative-decay-via-disorder-atom-arrays" itemprop="url"> <span class='span-link' itemprop="name">Modifying cooperative decay via disorder in atom arrays</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevA.109.013720" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevA.109.013720  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Gjonbalaj, Nik_O</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne_F</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-01-25">January 2024</time> , Physical Review A) </span> </div> <div class="actions" style="padding-left:10px;"> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10508183-harnessing-quantum-emitter-rings-efficient-energy-transport-trapping" itemprop="url"> <span class='span-link' itemprop="name">Harnessing quantum emitter rings for efficient energy transport and trapping</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1364/OPTICAQ.510021" target="_blank" title="Link to document DOI">https://doi.org/10.1364/OPTICAQ.510021  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Holzinger, Raphael</span> <span class="sep">; </span><span class="author" itemprop="author">Peter, Jonah S</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Ritsch, Helmut</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-01-01">January 2024</time> , Optica Quantum) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>Efficient transport and harvesting of excitation energy under low light conditions is an important process in nature and quantum technologies alike. Here we formulate a quantum optics perspective to excitation energy transport in configurations of two-level quantum emitters with a particular emphasis on efficiency and robustness against disorder. We study a periodic geometry of emitter rings with subwavelength spacing, where collective electronic states emerge due to near-field dipole–dipole interactions. The system gives rise to collective subradiant states that are particularly suited to excitation transport and are protected from energy disorder and radiative decoherence. Comparing ring geometries with other configurations shows that the former are more efficient in absorbing, transporting, and trapping incident light. Because our findings are agnostic as to the specific choice of quantum emitters, they indicate general design principles for quantum technologies with superior photon transport properties and may elucidate potential mechanisms resulting in the highly efficient energy transport efficiencies in natural light-harvesting systems.</p> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available January 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10536103-programmable-simulations-molecules-materials-reconfigurable-quantum-processors" itemprop="url"> <span class='span-link' itemprop="name">Programmable Simulations of Molecules and Materials with Reconfigurable Quantum Processors</span> </a> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Maskara, Nishad</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Shee, James</span> <span class="sep">; </span><span class="author" itemprop="author">Kalinowski, Marcin</span> <span class="sep">; </span><span class="author" itemprop="author">McClain_Gomez, Abigail</span> <span class="sep">; </span><span class="author" itemprop="author">Araiza_Bravo, Rodrigo</span> <span class="sep">; </span><span class="author" itemprop="author">Wang, Derek S</span> <span class="sep">; </span><span class="author" itemprop="author">Krylov, Anna I</span> <span class="sep">; </span><span class="author" itemprop="author">Yao, Norman Y</span> <span class="sep">; </span><span class="author" itemprop="author">Head-Gordon, Martin</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2023-12-04">December 2023</time> , arXivorg) </span> </div> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> <a class="misc" href="https://par.nsf.gov//servlets/purl/10536103" title="Link to document media" target="_blank"> <img class="ft_icon" alt="Accepted Manuscript" src="https://par.nsf.gov//img/ui/page_white_acrobat.png"/> Full Text Available</a> </span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10428867-dynamic-population-multiexcitation-subradiant-states-incoherently-excited-atomic-arrays" itemprop="url"> <span class='span-link' itemprop="name">Dynamic population of multiexcitation subradiant states in incoherently excited atomic arrays</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevA.107.L051701" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevA.107.L051701  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Rubies-Bigorda, Oriol</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne F.</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2023-05-01">May 2023</time> , Physical Review A) </span> </div> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevA.107.L051701" target="_blank" title="Link to document DOI" data-ostiid="10428867"> Full Text Available <span class="fas fa-external-link-alt"></span> </a> </span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10428879-characterizing-superradiant-dynamics-atomic-arrays-via-cumulant-expansion-approach" itemprop="url"> <span class='span-link' itemprop="name">Characterizing superradiant dynamics in atomic arrays via a cumulant expansion approach</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevResearch.5.013091" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevResearch.5.013091  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Rubies-Bigorda, Oriol</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne F.</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2023-02-01">February 2023</time> , Physical Review Research) </span> </div> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevResearch.5.013091" target="_blank" title="Link to document DOI" data-ostiid="10428879"> Full Text Available <span class="fas fa-external-link-alt"></span> </a> </span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10379333-optimized-geometries-cooperative-photon-storage-impurity-coupled-two-dimensional-atomic-array" itemprop="url"> <span class='span-link' itemprop="name">Optimized geometries for cooperative photon storage in an impurity coupled to a two-dimensional atomic array</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevA.106.053706" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevA.106.053706  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Buckley-Bonanno, Samuel</span> <span class="sep">; </span><span class="author" itemprop="author">Ostermann, Stefan</span> <span class="sep">; </span><span class="author" itemprop="author">Rubies-Bigorda, Oriol</span> <span class="sep">; </span><span class="author" itemprop="author">Patti, Taylor L.</span> <span class="sep">; </span><span class="author" itemprop="author">Yelin, Susanne F.</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2022-11-07">November 2022</time> , Physical Review A) </span> </div> <div class="actions" style="padding-left:10px;"> </div> </div><div class="clearfix"></div> </div> </li> </ol> <div id="pagination-lower" style=""> <div class="pull-right" style="line-height: 30px;"> <div class="btn-group pagination nomargin"> <a href="#" class="btn btn-sm btn-default noborderradius" disabled="disabled">«<span class="hidden-xs"> Prev</span></a> <a class="dropdown-toggle btn btn-sm btn-default paging-dropdown hidden-xs noborderradius" href="#" data-toggle="dropdown"><span class="caret"></span><span class="sr-only">Select page number</span></a> <div class="dropdown-menu pull-right paging-slider-dropdown" style="padding: 15px;"> <small> <div class="text-muted" style="line-height:20px;"><label for="pagination-sel-sptag-2">Go to page: <span class="paging-target">1</span> of <span class="paging-max">2</span></label></div> <div> <table> <tr> <td valign="top"> <input id="pagination-sel-sptag-2" data-range="" value="1" min="1" max="2" name="pagination-sel" type="range" class="pagination-sel noborderradius" style="height:26px;padding:0px;margin-right:5px; 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