[{"month":"01","oa":1,"title":"Anomalous multigap topological phases in periodically driven quantum rotors","article_processing_charge":"Yes (via OA deal)","date_published":"2026-01-12T00:00:00Z","OA_place":"publisher","doi":"10.1103/db9d-9bns","oa_version":"Published Version","article_type":"original","quality_controlled":"1","tmp":{"image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"ddc":["530"],"corr_author":"1","has_accepted_license":"1","type":"journal_article","year":"2026","publication_identifier":{"issn":["2469-9926"],"eissn":["2469-9934"]},"publication":"Physical Review A","publication_status":"published","fulldoi":"https://doi.org/10.1103/db9d-9bns","date_created":"2026-01-20T10:06:07Z","file":[{"relation":"main_file","content_type":"application/pdf","creator":"dernst","file_name":"2026_PhysicalReviewA_Karle.pdf","date_updated":"2026-01-21T09:04:48Z","success":1,"date_created":"2026-01-21T09:04:48Z","access_level":"open_access","checksum":"ca62a5050a234c0554e2583b1c126057","file_size":2650256,"file_id":"21029"}],"date_updated":"2026-07-29T08:59:30Z","PlanS_conform":"1","intvolume":"       113","volume":113,"related_material":{"record":[{"relation":"earlier_version","id":"19425","status":"public"}]},"arxiv":1,"abstract":[{"text":"We demonstrate that periodically driven quantum rotors provide a promising and broadly applicable platform to implement multigap topological phases, where groups of bands can acquire topological invariants due to non-Abelian braiding of band degeneracies. By adiabatically varying the periodic kicks to the rotor we find nodal-line braiding, which causes sign flips of topological charges of band nodes and can prevent them from annihilating, indicated by nonzero values of the patch Euler class. In particular, we report on the emergence of an anomalous Dirac string phase arising in the strongly driven regime, a truly out-of-equilibrium phase of the quantum rotor. This phase emanates from braiding processes involving all (quasienergy) gaps and manifests itself with edge states at zero angular momentum. Our results reveal direct applications in state-of-the-art experiments of quantum rotors, such as linear molecules driven by periodic far-off-resonant laser pulses or artificial quantum rotors in optical lattices, whose extensive versatility offers precise modification and observation of novel non-Abelian topological properties.","lang":"eng"}],"external_id":{"arxiv":["2408.16848"]},"OA_type":"hybrid","project":[{"call_identifier":"H2020","name":"Angulon: physics and applications of a new quasiparticle","_id":"2688CF98-B435-11E9-9278-68D0E5697425","grant_number":"801770"}],"status":"public","language":[{"iso":"eng"}],"author":[{"first_name":"Volker","orcid":"0000-0002-6963-0129","last_name":"Karle","full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425"},{"first_name":"Mikhail","orcid":"0000-0002-6990-7802","full_name":"Lemeshko, Mikhail","id":"37CB05FA-F248-11E8-B48F-1D18A9856A87","last_name":"Lemeshko"},{"first_name":"Adrien","last_name":"Bouhon","full_name":"Bouhon, Adrien"},{"first_name":"Robert-Jan","full_name":"Slager, Robert-Jan","last_name":"Slager"},{"last_name":"Ünal","full_name":"Ünal, F. Nur","first_name":"F. Nur"}],"file_date_updated":"2026-01-21T09:04:48Z","day":"12","publisher":"American Physical Society","scopus_import":"1","_id":"21009","department":[{"_id":"MiLe"}],"citation":{"chicago":"Karle, Volker, Mikhail Lemeshko, Adrien Bouhon, Robert-Jan Slager, and F. Nur Ünal. “Anomalous Multigap Topological Phases in Periodically Driven Quantum Rotors.” <i>Physical Review A</i>. American Physical Society, 2026. <a href=\"https://doi.org/10.1103/db9d-9bns\">https://doi.org/10.1103/db9d-9bns</a>.","ista":"Karle V, Lemeshko M, Bouhon A, Slager R-J, Ünal FN. 2026. Anomalous multigap topological phases in periodically driven quantum rotors. Physical Review A. 113(1), 012216.","short":"V. Karle, M. Lemeshko, A. Bouhon, R.-J. Slager, F.N. Ünal, Physical Review A 113 (2026).","apa":"Karle, V., Lemeshko, M., Bouhon, A., Slager, R.-J., &#38; Ünal, F. N. (2026). Anomalous multigap topological phases in periodically driven quantum rotors. <i>Physical Review A</i>. American Physical Society. <a href=\"https://doi.org/10.1103/db9d-9bns\">https://doi.org/10.1103/db9d-9bns</a>","ieee":"V. Karle, M. Lemeshko, A. Bouhon, R.-J. Slager, and F. N. Ünal, “Anomalous multigap topological phases in periodically driven quantum rotors,” <i>Physical Review A</i>, vol. 113, no. 1. American Physical Society, 2026.","mla":"Karle, Volker, et al. “Anomalous Multigap Topological Phases in Periodically Driven Quantum Rotors.” <i>Physical Review A</i>, vol. 113, no. 1, 012216, American Physical Society, 2026, doi:<a href=\"https://doi.org/10.1103/db9d-9bns\">10.1103/db9d-9bns</a>.","ama":"Karle V, Lemeshko M, Bouhon A, Slager R-J, Ünal FN. Anomalous multigap topological phases in periodically driven quantum rotors. <i>Physical Review A</i>. 2026;113(1). doi:<a href=\"https://doi.org/10.1103/db9d-9bns\">10.1103/db9d-9bns</a>"},"acknowledgement":"We thank G. M. Koutentakis, S. Wimberger, J. G. E. Harris, T. Enss, and A. Ghazaryan for fruitful discussions. M.L. acknowledges support by the European Research Council (ERC) Starting Grant No. 801770 (ANGULON). R.-J.S. acknowledges funding from a EPSRC ERC underwrite (Grant No. EP/X025829/1), a EPSRC New Investigator Award (Grant No. EP/W00187X/1), and Trinity College, Cambridge. F.N.Ü. acknowledges support from the Marie Skłodowska-Curie Programme of the European Commission (Grant No. 893915), a Simons Investigator Award (Grant No. 511029), Trinity College Cambridge, and the Royal Society (Grant No. URF/R1/241667).","ec_funded":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_number":"012216","issue":"1"},{"department":[{"_id":"GradSch"},{"_id":"MiLe"}],"_id":"19393","degree_awarded":"PhD","citation":{"ista":"Karle V. 2025. Non-equilibrium topological phases with periodically driven molecules and quantum rotors. Institute of Science and Technology Austria.","chicago":"Karle, Volker. “Non-Equilibrium Topological Phases with Periodically Driven Molecules and Quantum Rotors.” Institute of Science and Technology Austria, 2025. <a href=\"https://doi.org/10.15479/AT-ISTA-19393\">https://doi.org/10.15479/AT-ISTA-19393</a>.","ieee":"V. Karle, “Non-equilibrium topological phases with periodically driven molecules and quantum rotors,” Institute of Science and Technology Austria, 2025.","mla":"Karle, Volker. <i>Non-Equilibrium Topological Phases with Periodically Driven Molecules and Quantum Rotors</i>. Institute of Science and Technology Austria, 2025, doi:<a href=\"https://doi.org/10.15479/AT-ISTA-19393\">10.15479/AT-ISTA-19393</a>.","ama":"Karle V. Non-equilibrium topological phases with periodically driven molecules and quantum rotors. 2025. doi:<a href=\"https://doi.org/10.15479/AT-ISTA-19393\">10.15479/AT-ISTA-19393</a>","short":"V. Karle, Non-Equilibrium Topological Phases with Periodically Driven Molecules and Quantum Rotors, Institute of Science and Technology Austria, 2025.","apa":"Karle, V. (2025). <i>Non-equilibrium topological phases with periodically driven molecules and quantum rotors</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/AT-ISTA-19393\">https://doi.org/10.15479/AT-ISTA-19393</a>"},"publisher":"Institute of Science and Technology Austria","user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","alternative_title":["ISTA Thesis"],"abstract":[{"text":"Rotations constitute one of the fundamental symmetries in physics, characterized by their intricate group structure and infinite dimensional representations. In contrast to classical rotations, quantum mechanics unveils the SO(3) symmetry group structure, manifesting in phenomena without classical counterparts, from angular momentum quantization to non-trivial addition of angular momenta.\r\nWhile most studies of topological physics have focused on two-band systems, the SO(3) symmetry group of quantum rotors offers an inherently more complex platform with unprecedented possibilities for exploring topological phenomena. Despite their ubiquity in nature– from molecules to nanorotors– their potential for hosting topological phases has remained largely unexamined.\r\nIn this thesis, we mainly focus on periodically driven linear molecules as a prototype for studying topological phenomena in quantum rotors. Recent technological advances in coherent control of molecules, particularly through precisely shaped laser pulses, have made it possible to investigate linear rotors in the context of topology. While planar rotors have received some attention in recent years, threedimensional rotors–particularly linear molecules–harbor substantially richer topological phenomena due to their non-abelian nature and their additional angular degrees of freedom. We demonstrate that these systems can host novel edge states and topological features fundamentally impossible in planar systems.\r\nWe begin by establishing a theoretical bridge between periodically kicked rotors and \"crystalline\" lattices in angular momentum space. Using non-interacting linear molecules as our primary example, we show how quantum interference and revival patterns lead to the possibility to simulate band models with arbitrary number of bands N. While our framework applies to various quantum rotors, including nanorotors and kicked Bose-Einstein condensates, linear\r\nmolecules provide an ideal experimental platform due to their abovementioned precise controllability.\r\nThe core of this work examines adiabatic dynamics of 3D quantum rotors, establishing a geometric framework based on the Euler class to characterize its non-abelian topology. The non-Hermitian nature of the system enables novel braiding behaviors and topological transitions impossible in static systems, leading to an anomalous Dirac string phase with edge states in each gap, even though the Berry phases are all zero. These features can be directly observed through\r\nmolecular alignment and rotational level populations.\r\nThese findings establish quantum rotors as an alternative platform for studying multi-band topological physics, while suggesting practical implementations for quantum computation where topological protection could offer natural resilience against decoherence. The rich structure of three-dimensional rotation groups, combined with the tunability of topological features through driving parameters, makes this platform particularly valuable for exploring fundamental\r\nphysics and developing quantum technologies.","lang":"eng"}],"OA_type":"gold","language":[{"iso":"eng"}],"author":[{"id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425","full_name":"Karle, Volker","last_name":"Karle","orcid":"0000-0002-6963-0129","first_name":"Volker"}],"file_date_updated":"2025-03-20T08:02:35Z","day":"13","status":"public","publication_identifier":{"eissn":["2663-337X"]},"publication_status":"published","file":[{"access_level":"open_access","file_id":"19394","file_size":10625143,"checksum":"d3ab25782c7ea38ce9910e57d25f6733","date_updated":"2025-03-12T12:56:46Z","success":1,"file_name":"thesis_final.pdf","date_created":"2025-03-12T12:56:46Z","content_type":"application/pdf","creator":"vkarle","relation":"main_file"},{"content_type":"application/zip","creator":"vkarle","relation":"source_file","access_level":"closed","checksum":"3ccfb0aeba4d860d71e18347913034e4","file_size":23119202,"file_id":"19400","file_name":"thesis.zip","date_updated":"2025-03-20T08:02:35Z","date_created":"2025-03-13T13:15:10Z"}],"fulldoi":"https://doi.org/10.15479/AT-ISTA-19393","date_created":"2025-03-12T13:04:59Z","date_updated":"2026-07-29T08:59:30Z","type":"dissertation","year":"2025","related_material":{"record":[{"relation":"part_of_dissertation","id":"14851","status":"public"},{"id":"12788","status":"public","relation":"part_of_dissertation"},{"id":"9903","status":"public","relation":"part_of_dissertation"},{"id":"15004","status":"public","relation":"part_of_dissertation"},{"status":"public","id":"19425","relation":"part_of_dissertation"}]},"title":"Non-equilibrium topological phases with periodically driven molecules and quantum rotors","article_processing_charge":"No","month":"03","license":"https://creativecommons.org/licenses/by-nc-nd/4.0/","supervisor":[{"full_name":"Lemeshko, Mikhail","id":"37CB05FA-F248-11E8-B48F-1D18A9856A87","last_name":"Lemeshko","first_name":"Mikhail","orcid":"0000-0002-6990-7802"}],"oa":1,"oa_version":"Published Version","tmp":{"short":"CC BY-NC-ND (4.0)","name":"Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)","legal_code_url":"https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode","image":"/images/cc_by_nc_nd.png"},"ddc":["530"],"corr_author":"1","has_accepted_license":"1","page":"192","date_published":"2025-03-13T00:00:00Z","OA_place":"publisher","doi":"10.15479/AT-ISTA-19393"},{"year":"2024","type":"journal_article","date_updated":"2026-04-07T11:48:52Z","date_created":"2024-01-22T08:19:36Z","fulldoi":"https://doi.org/10.1002/piuz.202301690","file":[{"success":1,"date_updated":"2024-01-23T12:18:07Z","file_name":"2024_PhysikZeit_Karle.pdf","date_created":"2024-01-23T12:18:07Z","access_level":"open_access","file_size":1155244,"file_id":"14878","checksum":"3051dadcf9bc57da97e36b647c596ab1","relation":"main_file","content_type":"application/pdf","creator":"dernst"}],"publication_identifier":{"issn":["0031-9252"],"eissn":["1521-3943"]},"publication":"Physik in unserer Zeit","publication_status":"published","intvolume":"        55","related_material":{"record":[{"status":"public","id":"19393","relation":"dissertation_contains"}]},"volume":55,"oa":1,"month":"01","article_processing_charge":"Yes (via OA deal)","title":"Die faszinierende Topologie rotierender Quanten","keyword":["General Earth and Planetary Sciences","General Environmental Science"],"doi":"10.1002/piuz.202301690","date_published":"2024-01-01T00:00:00Z","page":"28-33","has_accepted_license":"1","corr_author":"1","tmp":{"image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"quality_controlled":"1","ddc":["530"],"article_type":"original","oa_version":"Published Version","publisher":"Wiley","citation":{"ista":"Karle V, Lemeshko M. 2024. Die faszinierende Topologie rotierender Quanten. Physik in unserer Zeit. 55(1), 28–33.","chicago":"Karle, Volker, and Mikhail Lemeshko. “Die faszinierende Topologie rotierender Quanten.” <i>Physik in unserer Zeit</i>. Wiley, 2024. <a href=\"https://doi.org/10.1002/piuz.202301690\">https://doi.org/10.1002/piuz.202301690</a>.","ama":"Karle V, Lemeshko M. Die faszinierende Topologie rotierender Quanten. <i>Physik in unserer Zeit</i>. 2024;55(1):28-33. doi:<a href=\"https://doi.org/10.1002/piuz.202301690\">10.1002/piuz.202301690</a>","ieee":"V. Karle and M. Lemeshko, “Die faszinierende Topologie rotierender Quanten,” <i>Physik in unserer Zeit</i>, vol. 55, no. 1. Wiley, pp. 28–33, 2024.","mla":"Karle, Volker, and Mikhail Lemeshko. “Die faszinierende Topologie rotierender Quanten.” <i>Physik in unserer Zeit</i>, vol. 55, no. 1, Wiley, 2024, pp. 28–33, doi:<a href=\"https://doi.org/10.1002/piuz.202301690\">10.1002/piuz.202301690</a>.","short":"V. Karle, M. Lemeshko, Physik in unserer Zeit 55 (2024) 28–33.","apa":"Karle, V., &#38; Lemeshko, M. (2024). Die faszinierende Topologie rotierender Quanten. <i>Physik in unserer Zeit</i>. Wiley. <a href=\"https://doi.org/10.1002/piuz.202301690\">https://doi.org/10.1002/piuz.202301690</a>"},"_id":"14851","department":[{"_id":"MiLe"}],"issue":"1","user_id":"3E5EF7F0-F248-11E8-B48F-1D18A9856A87","abstract":[{"lang":"ger","text":"Die Quantenrotation ist ein spannendes Phänomen, das in vielen verschiedenen Systemen auftritt, von Molekülen und Atomen bis hin zu subatomaren Teilchen wie Neutronen und Protonen. Durch den Einsatz von starken Laserpulsen ist es möglich, die mathematisch anspruchsvolle Topologie der Rotation von Molekülen aufzudecken und topologisch geschützte Zustände zu erzeugen, die unerwartetes Verhalten zeigen. Diese Entdeckungen könnten Auswirkungen auf die Molekülphysik und physikalische Chemie haben und die Entwicklung neuer Technologien ermöglichen. Die Verbindung von Quantenrotation und Topologie stellt ein aufregendes, interdisziplinäres Forschungsfeld dar und bietet neue Wege zur Kontrolle und Nutzung von quantenmechanischen Phänomenen."}],"status":"public","day":"01","file_date_updated":"2024-01-23T12:18:07Z","author":[{"full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425","last_name":"Karle","orcid":"0000-0002-6963-0129","first_name":"Volker"},{"last_name":"Lemeshko","id":"37CB05FA-F248-11E8-B48F-1D18A9856A87","full_name":"Lemeshko, Mikhail","first_name":"Mikhail","orcid":"0000-0002-6990-7802"}],"language":[{"iso":"ger"}]},{"day":"01","author":[{"last_name":"Karle","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425","full_name":"Karle, Volker","first_name":"Volker","orcid":"0000-0002-6963-0129"},{"first_name":"Mikhail","orcid":"0000-0002-6990-7802","last_name":"Lemeshko","full_name":"Lemeshko, Mikhail","id":"37CB05FA-F248-11E8-B48F-1D18A9856A87"}],"language":[{"iso":"eng"}],"project":[{"_id":"2688CF98-B435-11E9-9278-68D0E5697425","name":"Angulon: physics and applications of a new quasiparticle","call_identifier":"H2020","grant_number":"801770"}],"status":"public","abstract":[{"text":"The impulsive limit (the “sudden approximation”) has been widely employed to describe the interaction between molecules and short, far-off-resonant laser pulses. This approximation assumes that the timescale of the laser-molecule interaction is significantly shorter than the internal rotational period of the molecule, resulting in the rotational motion being instantaneously “frozen” during the interaction. This simplified description of the laser-molecule interaction is incorporated in various theoretical models predicting rotational dynamics of molecules driven by short laser pulses. In this theoretical work, we develop an effective theory for ultrashort laser pulses by examining the full time-evolution operator and solving the time-dependent Schrödinger equation at the operator level. Our findings reveal a critical angular momentum, lcrit, at which the impulsive limit breaks down. In other words, the validity of the sudden approximation depends not only on the pulse duration but also on its intensity, since the latter determines how many angular momentum states are populated. We explore both ultrashort multicycle (Gaussian) pulses and the somewhat less studied half-cycle pulses, which produce distinct effective potentials. We discuss the limitations of the impulsive limit and propose a method that rescales the effective matrix elements, enabling an improved and more accurate description of laser-molecule interactions.","lang":"eng"}],"external_id":{"isi":["001158043800006"],"arxiv":["2307.07256"]},"arxiv":1,"issue":"2","article_number":"023101","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ec_funded":1,"acknowledgement":"We thank Bretislav Friedrich, Marjan Mirahmadi, Artem Volosniev, and Burkhard Schmidt for insightful discussions. M.L. acknowledges support by the European Research Council (ERC) under Starting Grant No. 801770 (ANGULON).","citation":{"ama":"Karle V, Lemeshko M. Modeling laser pulses as δ kicks: Reevaluating the impulsive limit in molecular rotational dynamics. <i>Physical Review A</i>. 2024;109(2). doi:<a href=\"https://doi.org/10.1103/PhysRevA.109.023101\">10.1103/PhysRevA.109.023101</a>","ieee":"V. Karle and M. Lemeshko, “Modeling laser pulses as δ kicks: Reevaluating the impulsive limit in molecular rotational dynamics,” <i>Physical Review A</i>, vol. 109, no. 2. American Physical Society, 2024.","mla":"Karle, Volker, and Mikhail Lemeshko. “Modeling Laser Pulses as δ Kicks: Reevaluating the Impulsive Limit in Molecular Rotational Dynamics.” <i>Physical Review A</i>, vol. 109, no. 2, 023101, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PhysRevA.109.023101\">10.1103/PhysRevA.109.023101</a>.","apa":"Karle, V., &#38; Lemeshko, M. (2024). Modeling laser pulses as δ kicks: Reevaluating the impulsive limit in molecular rotational dynamics. <i>Physical Review A</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevA.109.023101\">https://doi.org/10.1103/PhysRevA.109.023101</a>","short":"V. Karle, M. Lemeshko, Physical Review A 109 (2024).","ista":"Karle V, Lemeshko M. 2024. Modeling laser pulses as δ kicks: Reevaluating the impulsive limit in molecular rotational dynamics. Physical Review A. 109(2), 023101.","chicago":"Karle, Volker, and Mikhail Lemeshko. “Modeling Laser Pulses as δ Kicks: Reevaluating the Impulsive Limit in Molecular Rotational Dynamics.” <i>Physical Review A</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PhysRevA.109.023101\">https://doi.org/10.1103/PhysRevA.109.023101</a>."},"department":[{"_id":"MiLe"}],"_id":"15004","scopus_import":"1","publisher":"American Physical Society","corr_author":"1","quality_controlled":"1","main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2307.07256"}],"article_type":"original","oa_version":"Preprint","doi":"10.1103/PhysRevA.109.023101","date_published":"2024-02-01T00:00:00Z","article_processing_charge":"No","title":"Modeling laser pulses as δ kicks: Reevaluating the impulsive limit in molecular rotational dynamics","oa":1,"month":"02","related_material":{"record":[{"id":"19393","status":"public","relation":"dissertation_contains"}]},"volume":109,"isi":1,"intvolume":"       109","date_updated":"2026-04-07T11:48:53Z","date_created":"2024-02-18T23:01:01Z","fulldoi":"https://doi.org/10.1103/PhysRevA.109.023101","publication_status":"published","publication":"Physical Review A","publication_identifier":{"eissn":["2469-9934"],"issn":["2469-9926"]},"year":"2024","type":"journal_article"},{"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_number":"2408.16848","ec_funded":1,"citation":{"mla":"Karle, Volker, et al. “Anomalous Multi-Gap Topological Phases in Periodically Driven Quantum  Rotors.” <i>ArXiv</i>, 2408.16848, doi:<a href=\"https://doi.org/10.48550/arXiv.2408.16848\">10.48550/arXiv.2408.16848</a>.","ieee":"V. Karle, M. Lemeshko, A. Bouhon, R.-J. Slager, and F. N. Ünal, “Anomalous multi-gap topological phases in periodically driven quantum  rotors,” <i>arXiv</i>. .","ama":"Karle V, Lemeshko M, Bouhon A, Slager R-J, Ünal FN. Anomalous multi-gap topological phases in periodically driven quantum  rotors. <i>arXiv</i>. doi:<a href=\"https://doi.org/10.48550/arXiv.2408.16848\">10.48550/arXiv.2408.16848</a>","apa":"Karle, V., Lemeshko, M., Bouhon, A., Slager, R.-J., &#38; Ünal, F. N. (n.d.). Anomalous multi-gap topological phases in periodically driven quantum  rotors. <i>arXiv</i>. <a href=\"https://doi.org/10.48550/arXiv.2408.16848\">https://doi.org/10.48550/arXiv.2408.16848</a>","short":"V. Karle, M. Lemeshko, A. Bouhon, R.-J. Slager, F.N. Ünal, ArXiv (n.d.).","ista":"Karle V, Lemeshko M, Bouhon A, Slager R-J, Ünal FN. Anomalous multi-gap topological phases in periodically driven quantum  rotors. arXiv, 2408.16848.","chicago":"Karle, Volker, Mikhail Lemeshko, Adrien Bouhon, Robert-Jan Slager, and F. Nur Ünal. “Anomalous Multi-Gap Topological Phases in Periodically Driven Quantum  Rotors.” <i>ArXiv</i>, n.d. <a href=\"https://doi.org/10.48550/arXiv.2408.16848\">https://doi.org/10.48550/arXiv.2408.16848</a>."},"acknowledgement":"We thank G. M. Koutentakis, S. Wimberger, J. G. E. Harris, T. Enss and A. Ghazaryan for fruitful discussions. M.L. acknowledges support by the European Research Council (ERC) Starting Grant No. 801770 (ANGULON). R.-J. S. acknowledges funding from a EPSRC ERC underwrite grant EP/X025829/1, a EPSRC New Investigator Award grant EP/W00187X/1, as well as Trinity College, Cambridge. F.N.U. acknowledges support from the Marie ¨Sk lodowska-Curie programme of the European Commission [Grant No. 893915], Simons Investigator Award\r\n[Grant No. 511029] and Trinity College Cambridge.","_id":"19425","department":[{"_id":"MiLe"}],"day":"29","language":[{"iso":"eng"}],"author":[{"orcid":"0000-0002-6963-0129","first_name":"Volker","last_name":"Karle","full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425"},{"orcid":"0000-0002-6990-7802","first_name":"Mikhail","last_name":"Lemeshko","id":"37CB05FA-F248-11E8-B48F-1D18A9856A87","full_name":"Lemeshko, Mikhail"},{"first_name":"Adrien","last_name":"Bouhon","full_name":"Bouhon, Adrien"},{"last_name":"Slager","full_name":"Slager, Robert-Jan","first_name":"Robert-Jan"},{"last_name":"Ünal","full_name":"Ünal, F. Nur","first_name":"F. Nur"}],"status":"public","project":[{"grant_number":"801770","call_identifier":"H2020","_id":"2688CF98-B435-11E9-9278-68D0E5697425","name":"Angulon: physics and applications of a new quasiparticle"}],"abstract":[{"lang":"eng","text":"We demonstrate that periodically driven quantum rotors provide a promising and broadly applicable platform to implement multi-gap topological phases, where groups of bands can acquire topological invariants due to non-Abelian braiding of band degeneracies. By adiabatically varying the periodic kicks to the rotor we find nodal-line braiding, which causes sign flips of topological charges of band nodes and can prevent them from annihilating, indicated by non-zero values of the %non-Abelian patch Euler class. In particular, we report\r\non the emergence of an anomalous Dirac string phase arising in the strongly driven regime, a truly out-of-equilibrium phase of the quantum rotor. This phase emanates from braiding processes involving all (quasienergy) gaps and manifests itself with edge states at zero angular momentum. Our results reveal direct applications in state-of-the-art experiments of quantum rotors, such as linear molecules driven by periodic far-off-resonant laser pulses or artificial\r\nquantum rotors in optical lattices, whose extensive versatility offers precise modification and observation of novel non-Abelian topological properties. "}],"external_id":{"arxiv":["2408.16848"]},"OA_type":"green","arxiv":1,"related_material":{"record":[{"id":"19393","status":"public","relation":"dissertation_contains"},{"relation":"later_version","status":"public","id":"21009"}]},"date_updated":"2026-07-29T08:59:31Z","publication":"arXiv","publication_status":"draft","fulldoi":"https://doi.org/10.48550/arXiv.2408.16848","date_created":"2025-03-20T07:48:23Z","type":"preprint","year":"2024","oa_version":"Preprint","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2408.16848","open_access":"1"}],"doi":"10.48550/arXiv.2408.16848","date_published":"2024-08-29T00:00:00Z","OA_place":"repository","article_processing_charge":"No","title":"Anomalous multi-gap topological phases in periodically driven quantum  rotors","oa":1,"month":"08"},{"language":[{"iso":"eng"}],"author":[{"first_name":"Volker","orcid":"0000-0002-6963-0129","full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425","last_name":"Karle"},{"first_name":"Areg","orcid":"0000-0001-9666-3543","last_name":"Ghazaryan","full_name":"Ghazaryan, Areg","id":"4AF46FD6-F248-11E8-B48F-1D18A9856A87"},{"id":"37CB05FA-F248-11E8-B48F-1D18A9856A87","full_name":"Lemeshko, Mikhail","last_name":"Lemeshko","first_name":"Mikhail","orcid":"0000-0002-6990-7802"}],"day":"10","status":"public","project":[{"_id":"2688CF98-B435-11E9-9278-68D0E5697425","name":"Angulon: physics and applications of a new quasiparticle","call_identifier":"H2020","grant_number":"801770"}],"abstract":[{"text":"We show that the simplest of existing molecules—closed-shell diatomics not interacting with one another—host topological charges when driven by periodic far-off-resonant laser pulses. A periodically kicked molecular rotor can be mapped onto a “crystalline” lattice in angular momentum space. This allows us to define quasimomenta and the band structure in the Floquet representation, by analogy with the Bloch waves of solid-state physics. Applying laser pulses spaced by 1/3 of the molecular rotational period creates a lattice with three atoms per unit cell with staggered hopping. Within the synthetic dimension of the laser strength, we discover Dirac cones with topological charges. These Dirac cones, topologically protected by reflection and time-reversal symmetry, are reminiscent of (although not equivalent to) that seen in graphene. They—and the corresponding edge states—are broadly tunable by adjusting the laser strength and can be observed in present-day experiments by measuring molecular alignment and populations of rotational levels. This paves the way to study controllable topological physics in gas-phase experiments with small molecules as well as to classify dynamical molecular states by their topological invariants.","lang":"eng"}],"external_id":{"arxiv":["2206.07067"],"pmid":["36962042"],"isi":["000957635500003"]},"arxiv":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_number":"103202","issue":"10","ec_funded":1,"_id":"12788","department":[{"_id":"MiLe"}],"scopus_import":"1","citation":{"chicago":"Karle, Volker, Areg Ghazaryan, and Mikhail Lemeshko. “Topological Charges of Periodically Kicked Molecules.” <i>Physical Review Letters</i>. American Physical Society, 2023. <a href=\"https://doi.org/10.1103/PhysRevLett.130.103202\">https://doi.org/10.1103/PhysRevLett.130.103202</a>.","ista":"Karle V, Ghazaryan A, Lemeshko M. 2023. Topological charges of periodically kicked molecules. Physical Review Letters. 130(10), 103202.","apa":"Karle, V., Ghazaryan, A., &#38; Lemeshko, M. (2023). Topological charges of periodically kicked molecules. <i>Physical Review Letters</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevLett.130.103202\">https://doi.org/10.1103/PhysRevLett.130.103202</a>","short":"V. Karle, A. Ghazaryan, M. Lemeshko, Physical Review Letters 130 (2023).","ama":"Karle V, Ghazaryan A, Lemeshko M. Topological charges of periodically kicked molecules. <i>Physical Review Letters</i>. 2023;130(10). doi:<a href=\"https://doi.org/10.1103/PhysRevLett.130.103202\">10.1103/PhysRevLett.130.103202</a>","ieee":"V. Karle, A. Ghazaryan, and M. Lemeshko, “Topological charges of periodically kicked molecules,” <i>Physical Review Letters</i>, vol. 130, no. 10. American Physical Society, 2023.","mla":"Karle, Volker, et al. “Topological Charges of Periodically Kicked Molecules.” <i>Physical Review Letters</i>, vol. 130, no. 10, 103202, American Physical Society, 2023, doi:<a href=\"https://doi.org/10.1103/PhysRevLett.130.103202\">10.1103/PhysRevLett.130.103202</a>."},"acknowledgement":"M. L. acknowledges support by the European Research Council (ERC) Starting Grant No. 801770 (ANGULON).","publisher":"American Physical Society","article_type":"original","oa_version":"Preprint","quality_controlled":"1","pmid":1,"main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2206.07067","open_access":"1"}],"corr_author":"1","date_published":"2023-03-10T00:00:00Z","doi":"10.1103/PhysRevLett.130.103202","title":"Topological charges of periodically kicked molecules","article_processing_charge":"No","month":"03","oa":1,"isi":1,"volume":130,"related_material":{"link":[{"relation":"press_release","description":"News on the ISTA website","url":"https://ista.ac.at/en/news/topology-of-rotating-molecules/"}],"record":[{"relation":"dissertation_contains","status":"public","id":"19393"}]},"intvolume":"       130","publication":"Physical Review Letters","publication_status":"published","publication_identifier":{"issn":["0031-9007"],"eissn":["1079-7114"]},"date_created":"2023-04-02T22:01:10Z","fulldoi":"https://doi.org/10.1103/PhysRevLett.130.103202","date_updated":"2026-04-07T11:48:53Z","type":"journal_article","year":"2023"},{"article_number":"060602","user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","issue":"6","ec_funded":1,"_id":"9903","scopus_import":"1","department":[{"_id":"MaSe"},{"_id":"GradSch"},{"_id":"MiLe"}],"acknowledgement":"We acknowledge useful discussions with V. Gritsev and A. Garkun and suggestions on implementation of the\r\nPPXPP model by D. Bluvstein. A. M. and M. S. were supported by the European Research Council (ERC) under\r\nthe European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899)","citation":{"ama":"Karle V, Serbyn M, Michailidis A. Area-law entangled eigenstates from nullspaces of local Hamiltonians. <i>Physical Review Letters</i>. 2021;127(6). doi:<a href=\"https://doi.org/10.1103/physrevlett.127.060602\">10.1103/physrevlett.127.060602</a>","ieee":"V. Karle, M. Serbyn, and A. Michailidis, “Area-law entangled eigenstates from nullspaces of local Hamiltonians,” <i>Physical Review Letters</i>, vol. 127, no. 6. American Physical Society, 2021.","mla":"Karle, Volker, et al. “Area-Law Entangled Eigenstates from Nullspaces of Local Hamiltonians.” <i>Physical Review Letters</i>, vol. 127, no. 6, 060602, American Physical Society, 2021, doi:<a href=\"https://doi.org/10.1103/physrevlett.127.060602\">10.1103/physrevlett.127.060602</a>.","short":"V. Karle, M. Serbyn, A. Michailidis, Physical Review Letters 127 (2021).","apa":"Karle, V., Serbyn, M., &#38; Michailidis, A. (2021). Area-law entangled eigenstates from nullspaces of local Hamiltonians. <i>Physical Review Letters</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevlett.127.060602\">https://doi.org/10.1103/physrevlett.127.060602</a>","ista":"Karle V, Serbyn M, Michailidis A. 2021. Area-law entangled eigenstates from nullspaces of local Hamiltonians. Physical Review Letters. 127(6), 060602.","chicago":"Karle, Volker, Maksym Serbyn, and Alexios Michailidis. “Area-Law Entangled Eigenstates from Nullspaces of Local Hamiltonians.” <i>Physical Review Letters</i>. American Physical Society, 2021. <a href=\"https://doi.org/10.1103/physrevlett.127.060602\">https://doi.org/10.1103/physrevlett.127.060602</a>."},"publisher":"American Physical Society","author":[{"first_name":"Volker","orcid":"0000-0002-6963-0129","last_name":"Karle","full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425"},{"first_name":"Maksym","orcid":"0000-0002-2399-5827","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","last_name":"Serbyn"},{"full_name":"Michailidis, Alexios","id":"36EBAD38-F248-11E8-B48F-1D18A9856A87","last_name":"Michailidis","first_name":"Alexios","orcid":"0000-0002-8443-1064"}],"language":[{"iso":"eng"}],"day":"06","file_date_updated":"2021-08-13T09:28:08Z","project":[{"call_identifier":"H2020","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","grant_number":"850899"}],"status":"public","abstract":[{"lang":"eng","text":"Eigenstate thermalization in quantum many-body systems implies that eigenstates at high energy are similar to random vectors. Identifying systems where at least some eigenstates are nonthermal is an outstanding question. In this Letter we show that interacting quantum models that have a nullspace—a degenerate subspace of eigenstates at zero energy (zero modes), which corresponds to infinite temperature, provide a route to nonthermal eigenstates. We analytically show the existence of a zero mode which can be represented as a matrix product state for a certain class of local Hamiltonians. In the more general case we use a subspace disentangling algorithm to generate an orthogonal basis of zero modes characterized by increasing entanglement entropy. We show evidence for an area-law entanglement scaling of the least-entangled zero mode in the broad parameter regime, leading to a conjecture that all local Hamiltonians with the nullspace feature zero modes with area-law entanglement scaling and, as such, break the strong thermalization hypothesis. Finally, we find zero modes in constrained models and propose a setup for observing their experimental signatures."}],"external_id":{"isi":["000684276000002"],"arxiv":["2102.13633"]},"arxiv":1,"isi":1,"volume":127,"related_material":{"record":[{"relation":"dissertation_contains","id":"19393","status":"public"}]},"intvolume":"       127","date_created":"2021-08-13T09:27:39Z","fulldoi":"https://doi.org/10.1103/physrevlett.127.060602","file":[{"success":1,"date_updated":"2021-08-13T09:28:08Z","file_name":"PhysRevLett.127.060602_SOM.pdf","date_created":"2021-08-13T09:28:08Z","access_level":"open_access","file_id":"9904","file_size":5064231,"checksum":"51218f302dcef99d90d1209809fcc874","relation":"main_file","creator":"mserbyn","content_type":"application/pdf"}],"publication_identifier":{"eissn":["1079-7114"],"issn":["0031-9007"]},"publication":"Physical Review Letters","publication_status":"published","date_updated":"2026-04-07T11:48:53Z","year":"2021","type":"journal_article","ddc":["539"],"tmp":{"image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"quality_controlled":"1","oa_version":"Published Version","article_type":"letter_note","has_accepted_license":"1","date_published":"2021-08-06T00:00:00Z","doi":"10.1103/physrevlett.127.060602","title":"Area-law entangled eigenstates from nullspaces of local Hamiltonians","article_processing_charge":"Yes (in subscription journal)","month":"08","oa":1},{"fulldoi":"https://doi.org/10.1098/rsos.200599","file":[{"file_name":"2020_RoyalSocOpenScience_Klose.pdf","success":1,"date_updated":"2020-11-09T09:07:11Z","date_created":"2020-11-09T09:07:11Z","access_level":"open_access","checksum":"5505c445de373bfd836eb4d3b48b1f37","file_size":1611485,"file_id":"8748","relation":"main_file","content_type":"application/pdf","creator":"dernst"}],"date_created":"2020-11-08T23:01:25Z","publication":"Royal Society Open Science","publication_status":"published","publication_identifier":{"eissn":["2054-5703"]},"date_updated":"2026-04-03T09:26:55Z","year":"2020","type":"journal_article","volume":7,"isi":1,"intvolume":"         7","title":"Emergence of cascading dynamics in interacting tipping elements of ecology and climate: Cascading dynamics in tipping elements","article_processing_charge":"No","month":"06","oa":1,"tmp":{"image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"quality_controlled":"1","ddc":["530","550"],"pmid":1,"oa_version":"Published Version","article_type":"original","has_accepted_license":"1","date_published":"2020-06-01T00:00:00Z","doi":"10.1098/rsos.200599","scopus_import":"1","_id":"8741","department":[{"_id":"MiLe"}],"acknowledgement":"V.K. thanks the German National Academic Foundation (Studienstiftung des deutschen Volkes) for financial\r\nsupport. J.F.D. is grateful for financial support by the Stordalen Foundation via the Planetary Boundary Research\r\nNetwork (PB.net), the Earth League’s EarthDoc program and the European Research Council Advanced Grant\r\nproject ERA (Earth Resilience in the Anthropocene). We are thankful for support by the Leibniz Association\r\n(project DominoES).\r\nAcknowledgements. This work has been performed in the context of the copan collaboration and the FutureLab on Earth\r\nResilience in the Anthropocene at the Potsdam Institute for Climate Impact Research. Furthermore, we acknowledge\r\ndiscussions with and helpful comments by N. Wunderling, J. Heitzig and M. Wiedermann.","citation":{"mla":"Klose, Ann Kristin, et al. “Emergence of Cascading Dynamics in Interacting Tipping Elements of Ecology and Climate: Cascading Dynamics in Tipping Elements.” <i>Royal Society Open Science</i>, vol. 7, no. 6, 200599, The Royal Society, 2020, doi:<a href=\"https://doi.org/10.1098/rsos.200599\">10.1098/rsos.200599</a>.","ieee":"A. K. Klose, V. Karle, R. Winkelmann, and J. F. Donges, “Emergence of cascading dynamics in interacting tipping elements of ecology and climate: Cascading dynamics in tipping elements,” <i>Royal Society Open Science</i>, vol. 7, no. 6. The Royal Society, 2020.","ama":"Klose AK, Karle V, Winkelmann R, Donges JF. Emergence of cascading dynamics in interacting tipping elements of ecology and climate: Cascading dynamics in tipping elements. <i>Royal Society Open Science</i>. 2020;7(6). doi:<a href=\"https://doi.org/10.1098/rsos.200599\">10.1098/rsos.200599</a>","apa":"Klose, A. K., Karle, V., Winkelmann, R., &#38; Donges, J. F. (2020). Emergence of cascading dynamics in interacting tipping elements of ecology and climate: Cascading dynamics in tipping elements. <i>Royal Society Open Science</i>. The Royal Society. <a href=\"https://doi.org/10.1098/rsos.200599\">https://doi.org/10.1098/rsos.200599</a>","short":"A.K. Klose, V. Karle, R. Winkelmann, J.F. Donges, Royal Society Open Science 7 (2020).","ista":"Klose AK, Karle V, Winkelmann R, Donges JF. 2020. Emergence of cascading dynamics in interacting tipping elements of ecology and climate: Cascading dynamics in tipping elements. Royal Society Open Science. 7(6), 200599.","chicago":"Klose, Ann Kristin, Volker Karle, Ricarda Winkelmann, and Jonathan F. Donges. “Emergence of Cascading Dynamics in Interacting Tipping Elements of Ecology and Climate: Cascading Dynamics in Tipping Elements.” <i>Royal Society Open Science</i>. The Royal Society, 2020. <a href=\"https://doi.org/10.1098/rsos.200599\">https://doi.org/10.1098/rsos.200599</a>."},"publisher":"The Royal Society","article_number":"200599","user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","issue":"6","external_id":{"arxiv":["1910.12042"],"isi":["000545625200001"],"pmid":["32742700"]},"abstract":[{"text":"In ecology, climate and other fields, (sub)systems have been identified that can transition into a qualitatively different state when a critical threshold or tipping point in a driving process is crossed. An understanding of those tipping elements is of great interest given the increasing influence of humans on the biophysical Earth system. Complex interactions exist between tipping elements, e.g. physical mechanisms connect subsystems of the climate system. Based on earlier work on such coupled nonlinear systems, we systematically assessed the qualitative long-term behaviour of interacting tipping elements. We developed an understanding of the consequences of interactions\r\non the tipping behaviour allowing for tipping cascades to emerge under certain conditions. The (narrative) application of\r\nthese qualitative results to real-world examples of interacting tipping elements indicates that tipping cascades with profound consequences may occur: the interacting Greenland ice sheet and thermohaline ocean circulation might tip before the tipping points of the isolated subsystems are crossed. The eutrophication of the first lake in a lake chain might propagate through the following lakes without a crossing of their individual critical nutrient input levels. The possibility of emerging cascading tipping dynamics calls for the development of a unified theory of interacting tipping elements and the quantitative analysis of interacting real-world tipping elements.","lang":"eng"}],"arxiv":1,"author":[{"last_name":"Klose","full_name":"Klose, Ann Kristin","first_name":"Ann Kristin"},{"orcid":"0000-0002-6963-0129","first_name":"Volker","full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425","last_name":"Karle"},{"full_name":"Winkelmann, Ricarda","last_name":"Winkelmann","first_name":"Ricarda"},{"full_name":"Donges, Jonathan F.","last_name":"Donges","first_name":"Jonathan F."}],"language":[{"iso":"eng"}],"day":"01","file_date_updated":"2020-11-09T09:07:11Z","status":"public"},{"type":"journal_article","year":"2019","date_updated":"2025-07-10T11:53:40Z","publication":"Physical Review A","publication_status":"published","publication_identifier":{"issn":["2469-9926"],"eissn":["2469-9934"]},"date_created":"2019-07-14T21:59:17Z","fulldoi":"https://doi.org/10.1103/PhysRevA.99.063627","intvolume":"        99","volume":99,"isi":1,"oa":1,"month":"06","article_processing_charge":"No","title":"Coupled superfluidity of binary Bose mixtures in two dimensions","doi":"10.1103/PhysRevA.99.063627","date_published":"2019-06-28T00:00:00Z","oa_version":"Preprint","main_file_link":[{"url":"https://arxiv.org/abs/1903.06759","open_access":"1"}],"quality_controlled":"1","publisher":"American Physical Society","citation":{"chicago":"Karle, Volker, Nicolò Defenu, and Tilman Enss. “Coupled Superfluidity of Binary Bose Mixtures in Two Dimensions.” <i>Physical Review A</i>. American Physical Society, 2019. <a href=\"https://doi.org/10.1103/PhysRevA.99.063627\">https://doi.org/10.1103/PhysRevA.99.063627</a>.","ista":"Karle V, Defenu N, Enss T. 2019. Coupled superfluidity of binary Bose mixtures in two dimensions. Physical Review A. 99(6), 063627.","apa":"Karle, V., Defenu, N., &#38; Enss, T. (2019). Coupled superfluidity of binary Bose mixtures in two dimensions. <i>Physical Review A</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevA.99.063627\">https://doi.org/10.1103/PhysRevA.99.063627</a>","short":"V. Karle, N. Defenu, T. Enss, Physical Review A 99 (2019).","ama":"Karle V, Defenu N, Enss T. Coupled superfluidity of binary Bose mixtures in two dimensions. <i>Physical Review A</i>. 2019;99(6). doi:<a href=\"https://doi.org/10.1103/PhysRevA.99.063627\">10.1103/PhysRevA.99.063627</a>","ieee":"V. Karle, N. Defenu, and T. Enss, “Coupled superfluidity of binary Bose mixtures in two dimensions,” <i>Physical Review A</i>, vol. 99, no. 6. American Physical Society, 2019.","mla":"Karle, Volker, et al. “Coupled Superfluidity of Binary Bose Mixtures in Two Dimensions.” <i>Physical Review A</i>, vol. 99, no. 6, 063627, American Physical Society, 2019, doi:<a href=\"https://doi.org/10.1103/PhysRevA.99.063627\">10.1103/PhysRevA.99.063627</a>."},"_id":"6632","department":[{"_id":"MiLe"}],"scopus_import":"1","issue":"6","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_number":"063627","arxiv":1,"abstract":[{"text":"We consider a two-component Bose gas in two dimensions at a low temperature with short-range repulsive interaction. In the coexistence phase where both components are superfluid, interspecies interactions induce a nondissipative drag between the two superfluid flows (Andreev-Bashkin effect). We show that this behavior leads to a modification of the usual Berezinskii-Kosterlitz-Thouless (BKT) transition in two dimensions. We extend the renormalization of the superfluid densities at finite temperature using the renormalization-group approach and find that the vortices of one component have a large influence on the superfluid properties of the other, mediated  by  the  nondissipative  drag.  The  extended  BKT  flow  equations  indicate  that  the  occurrence  of  the vortex unbinding transition in one of the components can induce the breakdown of superfluidity also in the other, leading to a locking phenomenon for the critical temperatures of the two gases.","lang":"eng"}],"external_id":{"arxiv":["1903.06759"],"isi":["000473133600007"]},"status":"public","day":"28","language":[{"iso":"eng"}],"author":[{"first_name":"Volker","orcid":"0000-0002-6963-0129","full_name":"Karle, Volker","id":"D7C012AE-D7ED-11E9-95E8-1EC5E5697425","last_name":"Karle"},{"last_name":"Defenu","full_name":"Defenu, Nicolò","first_name":"Nicolò"},{"full_name":"Enss, Tilman","last_name":"Enss","first_name":"Tilman"}]}]