[{"external_id":{"arxiv":["2504.02460"]},"issue":"4","file":[{"creator":"dernst","content_type":"application/pdf","date_updated":"2025-12-01T08:00:19Z","checksum":"c4e582ab64ab9f8fface70bf2fd31882","access_level":"open_access","relation":"main_file","date_created":"2025-12-01T08:00:19Z","file_size":483879,"file_name":"2025_PhysReviewResearch_Brighi.pdf","success":1,"file_id":"20715"}],"intvolume":"         7","_id":"20709","status":"public","oa_version":"Published Version","arxiv":1,"day":"01","year":"2025","citation":{"chicago":"Brighi, Pietro, Marko Ljubotina, Federico Roccati, and Federico Balducci. “Finite Steady-State Current Defies Non-Hermitian Many-Body Localization.” <i>Physical Review Research</i>. American Physical Society, 2025. <a href=\"https://doi.org/10.1103/crwj-x7j8\">https://doi.org/10.1103/crwj-x7j8</a>.","short":"P. Brighi, M. Ljubotina, F. Roccati, F. Balducci, Physical Review Research 7 (2025).","mla":"Brighi, Pietro, et al. “Finite Steady-State Current Defies Non-Hermitian Many-Body Localization.” <i>Physical Review Research</i>, vol. 7, no. 4, L042014, American Physical Society, 2025, doi:<a href=\"https://doi.org/10.1103/crwj-x7j8\">10.1103/crwj-x7j8</a>.","ama":"Brighi P, Ljubotina M, Roccati F, Balducci F. Finite steady-state current defies non-Hermitian many-body localization. <i>Physical Review Research</i>. 2025;7(4). doi:<a href=\"https://doi.org/10.1103/crwj-x7j8\">10.1103/crwj-x7j8</a>","ista":"Brighi P, Ljubotina M, Roccati F, Balducci F. 2025. Finite steady-state current defies non-Hermitian many-body localization. Physical Review Research. 7(4), L042014.","apa":"Brighi, P., Ljubotina, M., Roccati, F., &#38; Balducci, F. (2025). Finite steady-state current defies non-Hermitian many-body localization. <i>Physical Review Research</i>. American Physical Society. <a href=\"https://doi.org/10.1103/crwj-x7j8\">https://doi.org/10.1103/crwj-x7j8</a>","ieee":"P. Brighi, M. Ljubotina, F. Roccati, and F. Balducci, “Finite steady-state current defies non-Hermitian many-body localization,” <i>Physical Review Research</i>, vol. 7, no. 4. American Physical Society, 2025."},"acknowledgement":"F.B. thanks Giuseppe de Tomasi and Oskar A. Prośniak for discussion. P.B. acknowledges support by the Austrian Science Fund (FWF) (Grant Agreement No. 10.55776/ESP9057324). This research was funded in whole or in part by the Austrian Science Fund (FWF) [10.55776/COE1]. The numerical simulations were performed using the ITensor library [73] on the Vienna Scientific Cluster (VSC) and on the MPIPKS HPC cluster. M.L. acknowledges support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC-2111—390814868. F.R. acknowledges support by the European Union-Next Generation EU with the project “Quantum Optics in Many-Body photonic Environments” (QOMBE) code SOE2024_0000084-CUP B77G24000480006. Open\r\naccess publication funded by Max Planck Society.","publisher":"American Physical Society","ddc":["530"],"date_published":"2025-10-01T00:00:00Z","PlanS_conform":"1","has_accepted_license":"1","OA_type":"gold","fulldoi":"https://doi.org/10.1103/crwj-x7j8","article_type":"original","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"OA_place":"publisher","DOAJ_listed":"1","date_updated":"2026-09-16T07:06:16Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","abstract":[{"text":"Non-Hermitian many-body localization (NH MBL) has emerged as a possible scenario for stable localization in open systems, as suggested by spectral indicators identifying a putative transition for finite system sizes. In this work, we shift the focus to dynamical probes, specifically the steady-state spin current, to investigate transport properties in a disordered, non-Hermitian XXZ spin chain. Through exact diagonalization for small systems and tensor-network methods for larger chains, we demonstrate that the steady-state current remains finite and decays exponentially with disorder strength, showing no evidence of a transition up to disorder values far beyond the previously claimed critical point. Our results reveal a stark discrepancy between spectral indicators, which suggest localization, and transport behavior, which indicates delocalization. This highlights the importance of dynamical observables in characterizing NH MBL and suggests that traditional spectral measures may not fully capture the physics of non-Hermitian systems. Additionally, we observe a noncommutativity of limits in system size and time, further complicating the interpretation of finite-size studies. These findings challenge the existence of NH MBL in the studied model and underscore the need for alternative approaches to understanding localization in non-Hermitian settings.","lang":"eng"}],"file_date_updated":"2025-12-01T08:00:19Z","date_created":"2025-11-30T23:02:08Z","article_processing_charge":"Yes (via OA deal)","project":[{"grant_number":"COE01","_id":"92c64506-16d5-11f0-9cad-87ce313ee832","name":"Quantum Science Austria (Serbyn)"}],"quality_controlled":"1","language":[{"iso":"eng"}],"volume":7,"department":[{"_id":"MaSe"}],"publication_status":"published","month":"10","license":"https://creativecommons.org/licenses/by/4.0/","publication_identifier":{"eissn":["2643-1564"]},"oa":1,"title":"Finite steady-state current defies non-Hermitian many-body localization","doi":"10.1103/crwj-x7j8","type":"journal_article","article_number":"L042014","scopus_import":"1","publication":"Physical Review Research","author":[{"first_name":"Pietro","orcid":"0000-0002-7969-2729","last_name":"Brighi","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","full_name":"Brighi, Pietro"},{"full_name":"Ljubotina, Marko","last_name":"Ljubotina","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","orcid":"0000-0003-0038-7068","first_name":"Marko"},{"last_name":"Roccati","full_name":"Roccati, Federico","first_name":"Federico"},{"full_name":"Balducci, Federico","last_name":"Balducci","first_name":"Federico"}]},{"date_published":"2025-01-21T00:00:00Z","OA_type":"hybrid","has_accepted_license":"1","ddc":["530"],"tmp":{"legal_code_url":"https://creativecommons.org/licenses/by-nc/3.0/legalcode","short":"CC BY-NC (3.0)","name":"Creative Commons Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)","image":"/images/cc_by_nc.png"},"article_type":"original","fulldoi":"https://doi.org/10.1039/d4cp03727h","OA_place":"publisher","date_updated":"2026-10-21T07:56:55Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","abstract":[{"lang":"eng","text":"We present an ab initio theoretical method to calculate the resonant Auger spectrum in the presence of ultrafast dissociation. The method is demonstrated by deriving the L-VV resonant Auger spectrum mediated by the 2p3/2−1σ* resonance in HCl, where the electronic Auger decay and nuclear dissociation occur on the same time scale. The Auger decay rates are calculated within the one-center approximation and are shown to vary significantly with the inter-nuclear distance. A quantum-mechanical description of dissociation is effectuated by propagating the corresponding Franck–Condon factors. The calculated profiles of Auger spectral lines resemble those of atomic Auger decay but here the characteristic tails extend towards lower electron kinetic energies, which reflect specific features of the potential energy curves. The presented method can describe the resonant Auger spectrum for an arbitrary speed of dissociation and simplifies to known approximations in the limiting cases."}],"ec_funded":1,"file_date_updated":"2025-04-16T09:46:45Z","dataavailabilitystatement":"Data for this article, including potential energy curves, Auger decay rates and spectral lines, are available at ZENODO at https://doi.org/10.5281/zenodo.13833475.","issue":"3","external_id":{"pmid":["39698879"],"isi":["001379819100001"]},"intvolume":"        27","file":[{"success":1,"file_id":"19581","file_size":1270582,"date_created":"2025-04-16T09:46:45Z","file_name":"2025_PCCP_Hrast.pdf","access_level":"open_access","checksum":"d035683179547b41b811107a8649aab0","relation":"main_file","creator":"dernst","content_type":"application/pdf","date_updated":"2025-04-16T09:46:45Z"}],"_id":"18710","status":"public","researchdata_availability":"yes","oa_version":"Published Version","isi":1,"day":"21","das_tickbox":"1","publisher":"Royal Society of Chemistry","citation":{"ista":"Hrast M, Ljubotina M, Zitnik M. 2025. Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl. Physical Chemistry Chemical Physics. 27(3), 1473–1482.","ama":"Hrast M, Ljubotina M, Zitnik M. Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl. <i>Physical Chemistry Chemical Physics</i>. 2025;27(3):1473-1482. doi:<a href=\"https://doi.org/10.1039/d4cp03727h\">10.1039/d4cp03727h</a>","ieee":"M. Hrast, M. Ljubotina, and M. Zitnik, “Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl,” <i>Physical Chemistry Chemical Physics</i>, vol. 27, no. 3. Royal Society of Chemistry, pp. 1473–1482, 2025.","apa":"Hrast, M., Ljubotina, M., &#38; Zitnik, M. (2025). Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl. <i>Physical Chemistry Chemical Physics</i>. Royal Society of Chemistry. <a href=\"https://doi.org/10.1039/d4cp03727h\">https://doi.org/10.1039/d4cp03727h</a>","chicago":"Hrast, Mateja, Marko Ljubotina, and Matjaz Zitnik. “Ab Initio Auger Spectrum of the Ultrafast Dissociating 2p3/2−1σ* Resonance in HCl.” <i>Physical Chemistry Chemical Physics</i>. Royal Society of Chemistry, 2025. <a href=\"https://doi.org/10.1039/d4cp03727h\">https://doi.org/10.1039/d4cp03727h</a>.","mla":"Hrast, Mateja, et al. “Ab Initio Auger Spectrum of the Ultrafast Dissociating 2p3/2−1σ* Resonance in HCl.” <i>Physical Chemistry Chemical Physics</i>, vol. 27, no. 3, Royal Society of Chemistry, 2025, pp. 1473–82, doi:<a href=\"https://doi.org/10.1039/d4cp03727h\">10.1039/d4cp03727h</a>.","short":"M. Hrast, M. Ljubotina, M. Zitnik, Physical Chemistry Chemical Physics 27 (2025) 1473–1482."},"year":"2025","acknowledgement":"This publication is based upon work from COST Action CA18212 – Molecular Dynamics in the GAS phase (MD-GAS), supported by COST (European Cooperation in Science and Technology). This work was financially supported by the Slovenian Research Agency in the framework of research program P1-0112 Studies of Atoms, Molecules and Structures by Photons and Particles. Part of this work was financed by the European Research Council (ERC) through the Starting Grant No. 801770 (ANGULON). The authors acknowledge P. Lablanquie, H. Iwayama, F. Penent, K. Soejima and E. Shigemasa for sharing their unpublished experimental spectra on HCl.","title":"Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl","oa":1,"publication_identifier":{"issn":["1463-9076"]},"pmid":1,"type":"journal_article","doi":"10.1039/d4cp03727h","corr_author":"1","scopus_import":"1","publication":"Physical Chemistry Chemical Physics","author":[{"first_name":"Mateja","last_name":"Hrast","id":"48dbb294-2a9c-11ef-905d-f56be71f0e5d","full_name":"Hrast, Mateja"},{"full_name":"Ljubotina, Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","last_name":"Ljubotina","orcid":"0000-0003-0038-7068","first_name":"Marko"},{"first_name":"Matjaz","full_name":"Zitnik, Matjaz","last_name":"Zitnik"}],"article_processing_charge":"Yes (via OA deal)","date_created":"2024-12-29T23:01:58Z","supplementarymaterial":"no","project":[{"grant_number":"801770","call_identifier":"H2020","name":"Angulon: physics and applications of a new quasiparticle","_id":"2688CF98-B435-11E9-9278-68D0E5697425"}],"related_material":{"record":[{"status":"public","relation":"research_data","id":"18716"},{"relation":"research_data","id":"22866","status":"public"}]},"quality_controlled":"1","page":"1473-1482","publication_status":"published","volume":27,"language":[{"iso":"eng"}],"department":[{"_id":"MiLe"},{"_id":"MaSe"}],"month":"01","license":"https://creativecommons.org/licenses/by-nc/3.0/"},{"ddc":["530"],"has_accepted_license":"1","OA_type":"gold","date_published":"2024-10-23T00:00:00Z","fulldoi":"https://doi.org/10.1103/prxquantum.5.040311","article_type":"original","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"OA_place":"publisher","DOAJ_listed":"1","date_updated":"2026-10-16T12:13:31Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","file_date_updated":"2024-10-30T08:59:09Z","ec_funded":1,"abstract":[{"text":"The advancement of quantum simulators motivates the development of a theoretical framework to assist with efficient state preparation in quantum many-body systems. Generally, preparing a target entangled state via unitary evolution with time-dependent couplings is a challenging task and very little is known about the existence of solutions and their properties. In this work we develop a constructive approach for preparing matrix product states (MPS) via continuous unitary evolution. We provide an explicit construction of the operator that exactly implements the evolution of a given MPS along a specified direction in its tangent space. This operator can be written as a sum of local terms of finite range, yet it is in general non-Hermitian. Relying on the explicit construction of the non-Hermitian generator of the dynamics, we demonstrate the existence of a Hermitian sequence of operators that implements the desired MPS evolution with an error that decreases exponentially with the operator range. The construction is benchmarked on an explicit periodic trajectory in a translationally invariant MPS manifold. We demonstrate that the Floquet unitary generating the dynamics over one period of the trajectory features an approximate MPS-like eigenstate embedded among a sea of thermalizing eigenstates. These results show that our construction is not only useful for state preparation and control of many-body systems, but also provides a generic route towards Floquet scars—periodically driven models with quasilocal generators of dynamics that have exact MPS eigenstates in their spectrum.","lang":"eng"}],"external_id":{"isi":["001346198800001"],"arxiv":["2403.12325"]},"issue":"4","file":[{"access_level":"open_access","checksum":"2e057ba021744d0a74602517935326b3","relation":"main_file","date_updated":"2024-10-30T08:59:09Z","content_type":"application/pdf","creator":"dernst","success":1,"file_id":"18489","file_name":"2024_PRXQuantum_Ljubotina.pdf","date_created":"2024-10-30T08:59:09Z","file_size":1151431}],"intvolume":"         5","_id":"18488","status":"public","researchdata_availability":"no","oa_version":"Published Version","day":"23","arxiv":1,"das_tickbox":"0","isi":1,"year":"2024","acknowledgement":"We thank L. Piroli, S. Garratt, and A. Molnár for insightful discussions. This research was funded in part by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreements No. 850899 and No. 863476), the Austrian Science Fund (FWF) (Grant DOIs 10.55776/COE1, 10.55776/P36305, and 10.55776/F71), and the European Union (NextGenerationEU). This work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation Grant PHY-2210452. This research was supported in part by NSF Grant PHY-2309135 to the Kavli Institute for Theoretical Physics (KITP).","citation":{"ieee":"M. Ljubotina, E. Petrova, N. Schuch, and M. Serbyn, “Tangent space generators of matrix product states and exact floquet quantum scars,” <i>PRX Quantum</i>, vol. 5, no. 4. American Physical Society, 2024.","apa":"Ljubotina, M., Petrova, E., Schuch, N., &#38; Serbyn, M. (2024). Tangent space generators of matrix product states and exact floquet quantum scars. <i>PRX Quantum</i>. American Physical Society. <a href=\"https://doi.org/10.1103/prxquantum.5.040311\">https://doi.org/10.1103/prxquantum.5.040311</a>","ama":"Ljubotina M, Petrova E, Schuch N, Serbyn M. Tangent space generators of matrix product states and exact floquet quantum scars. <i>PRX Quantum</i>. 2024;5(4). doi:<a href=\"https://doi.org/10.1103/prxquantum.5.040311\">10.1103/prxquantum.5.040311</a>","ista":"Ljubotina M, Petrova E, Schuch N, Serbyn M. 2024. Tangent space generators of matrix product states and exact floquet quantum scars. PRX Quantum. 5(4), 040311.","mla":"Ljubotina, Marko, et al. “Tangent Space Generators of Matrix Product States and Exact Floquet Quantum Scars.” <i>PRX Quantum</i>, vol. 5, no. 4, 040311, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/prxquantum.5.040311\">10.1103/prxquantum.5.040311</a>.","short":"M. Ljubotina, E. Petrova, N. Schuch, M. Serbyn, PRX Quantum 5 (2024).","chicago":"Ljubotina, Marko, Elena Petrova, Norbert Schuch, and Maksym Serbyn. “Tangent Space Generators of Matrix Product States and Exact Floquet Quantum Scars.” <i>PRX Quantum</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/prxquantum.5.040311\">https://doi.org/10.1103/prxquantum.5.040311</a>."},"publisher":"American Physical Society","publication_identifier":{"eissn":["2691-3399"]},"title":"Tangent space generators of matrix product states and exact floquet quantum scars","oa":1,"doi":"10.1103/prxquantum.5.040311","type":"journal_article","article_number":"040311","corr_author":"1","scopus_import":"1","publication":"PRX Quantum","author":[{"first_name":"Marko","orcid":"0000-0003-0038-7068","full_name":"Ljubotina, Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","last_name":"Ljubotina"},{"first_name":"Elena","full_name":"Petrova, Elena","last_name":"Petrova","id":"0ac84990-897b-11ed-a09c-f5abb56a4ede"},{"first_name":"Norbert","full_name":"Schuch, Norbert","last_name":"Schuch"},{"id":"47809E7E-F248-11E8-B48F-1D18A9856A87","last_name":"Serbyn","full_name":"Serbyn, Maksym","orcid":"0000-0002-2399-5827","first_name":"Maksym"}],"supplementarymaterial":"yes","date_created":"2024-10-29T16:04:05Z","APC_amount":"3711,01 EUR","article_processing_charge":"Yes","project":[{"grant_number":"850899","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","call_identifier":"H2020"}],"quality_controlled":"1","department":[{"_id":"MaSe"}],"language":[{"iso":"eng"}],"volume":5,"publication_status":"published","month":"10"},{"publication_identifier":{"eissn":["2691-3399"]},"title":"Quantum many-body spin ratchets","oa":1,"doi":"10.1103/PRXQuantum.5.030356","type":"journal_article","article_number":"030356","scopus_import":"1","publication":"PRX Quantum","author":[{"last_name":"Zadnik","full_name":"Zadnik, Lenart","first_name":"Lenart"},{"id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","last_name":"Ljubotina","full_name":"Ljubotina, Marko","first_name":"Marko","orcid":"0000-0003-0038-7068"},{"last_name":"Krajnik","full_name":"Krajnik, Žiga","first_name":"Žiga"},{"first_name":"Enej","full_name":"Ilievski, Enej","last_name":"Ilievski"},{"first_name":"Tomaž","last_name":"Prosen","full_name":"Prosen, Tomaž"}],"date_created":"2024-10-06T22:01:12Z","supplementarymaterial":"yes","article_processing_charge":"Yes","project":[{"grant_number":"850899","call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control"}],"quality_controlled":"1","language":[{"iso":"eng"}],"department":[{"_id":"MaSe"}],"volume":5,"publication_status":"published","month":"09","ddc":["530"],"date_published":"2024-09-25T00:00:00Z","OA_type":"gold","has_accepted_license":"1","article_type":"original","fulldoi":"https://doi.org/10.1103/PRXQuantum.5.030356","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"OA_place":"publisher","DOAJ_listed":"1","date_updated":"2026-10-16T12:13:08Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ec_funded":1,"file_date_updated":"2024-10-07T11:04:12Z","abstract":[{"text":"Introducing a class of SU(2) invariant quantum unitary circuits generating chiral transport, we examine the role of broken space-reflection and time-reversal symmetries on spin-transport properties. Upon adjusting parameters of local unitary gates, the dynamics can be either chaotic or integrable. The latter corresponds to a generalization of the space-time discretized (Trotterized) higher-spin quantum Heisenberg chain. We demonstrate that breaking of space-reflection symmetry results in a drift in the dynamical spin susceptibility. Remarkably, we find a universal drift velocity given by a simple formula, which, at zero average magnetization, depends only on the values of SU(2) Casimir invariants associated with local spins. In the integrable case, the drift velocity formula is confirmed analytically based on the exact solution of thermodynamic Bethe ansatz equations. Finally, by inspecting the large fluctuations of the time-integrated current between two halves of the system in stationary maximum-entropy states, we demonstrate violation of the Gallavotti-Cohen symmetry, implying that such states cannot be regarded as equilibrium ones. We show that the scaled cumulant generating function of the time-integrated current instead obeys a generalized fluctuation relation.","lang":"eng"}],"external_id":{"arxiv":["2406.01571"],"isi":["001327172800001"]},"issue":"3","file":[{"access_level":"open_access","checksum":"bc230631255d3bcf8bcbbc8fdbfefcf2","relation":"main_file","creator":"dernst","content_type":"application/pdf","date_updated":"2024-10-07T11:04:12Z","success":1,"file_id":"18183","file_size":1061648,"date_created":"2024-10-07T11:04:12Z","file_name":"2024_PRXQuantum_Zadnik.pdf"}],"intvolume":"         5","_id":"18176","status":"public","researchdata_availability":"no","oa_version":"Published Version","das_tickbox":"0","arxiv":1,"day":"25","isi":1,"year":"2024","acknowledgement":"The authors thank Denis Bernard, Jérôme Dubail, Hosho Katsura, Kareljan Schoutens, and Alberto Zorzato for stimulating discussions. This work has been supported by: Slovenian Research Agency (ARIS) under Grants No. N1-0219 (T.P., L.Z.), No. N1-0334 (T.P., L.Z.), No. N1-0243 (E.I.), and under Research Program P1-0402 (E.I., T.P., L.Z.). European Research Council (ERC) under Consolidator Grant No. 771536—NEMO (L.Z.), Advanced Grant No.\r\n101096208—QUEST (T.P., L.Z.), and Starting Grant No. 850899—NEQuM (M.L.). Simons Foundation under Simons Junior Fellowship Grant No. 1141511 (Ž.K.). M.L. acknowledges the hospitality of the Aspen Center for Physics, which is supported by National Science Foundation Grant No. PHY-2210452. Numerical simulations were performed using the ITensor library [117]. ","citation":{"chicago":"Zadnik, Lenart, Marko Ljubotina, Žiga Krajnik, Enej Ilievski, and Tomaž Prosen. “Quantum Many-Body Spin Ratchets.” <i>PRX Quantum</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PRXQuantum.5.030356\">https://doi.org/10.1103/PRXQuantum.5.030356</a>.","short":"L. Zadnik, M. Ljubotina, Ž. Krajnik, E. Ilievski, T. Prosen, PRX Quantum 5 (2024).","mla":"Zadnik, Lenart, et al. “Quantum Many-Body Spin Ratchets.” <i>PRX Quantum</i>, vol. 5, no. 3, 030356, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PRXQuantum.5.030356\">10.1103/PRXQuantum.5.030356</a>.","ista":"Zadnik L, Ljubotina M, Krajnik Ž, Ilievski E, Prosen T. 2024. Quantum many-body spin ratchets. PRX Quantum. 5(3), 030356.","ama":"Zadnik L, Ljubotina M, Krajnik Ž, Ilievski E, Prosen T. Quantum many-body spin ratchets. <i>PRX Quantum</i>. 2024;5(3). doi:<a href=\"https://doi.org/10.1103/PRXQuantum.5.030356\">10.1103/PRXQuantum.5.030356</a>","apa":"Zadnik, L., Ljubotina, M., Krajnik, Ž., Ilievski, E., &#38; Prosen, T. (2024). Quantum many-body spin ratchets. <i>PRX Quantum</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PRXQuantum.5.030356\">https://doi.org/10.1103/PRXQuantum.5.030356</a>","ieee":"L. Zadnik, M. Ljubotina, Ž. Krajnik, E. Ilievski, and T. Prosen, “Quantum many-body spin ratchets,” <i>PRX Quantum</i>, vol. 5, no. 3. American Physical Society, 2024."},"publisher":"American Physical Society"},{"abstract":[{"text":"Quantum computers are increasing in size and quality but are still very noisy. Error mitigation extends the size of the quantum circuits that noisy devices can meaningfully execute. However, state-of-the-art error mitigation methods are hard to implement and the limited qubit connectivity in superconducting qubit devices restricts most applications to the hardware's native topology. Here we show a quantum approximate optimization algorithm (QAOA) on nonplanar random regular graphs with up to 40 nodes enabled by a machine learning-based error mitigation. We use a swap network with careful decision-variable-to-qubit mapping and a feed-forward neural network to optimize a depth-two QAOA on up to 40 qubits. We observe a meaningful parameter optimization for the largest graph which requires running quantum circuits with 958 two-qubit gates. Our paper emphasizes the need to mitigate samples, and not only expectation values, in quantum approximate optimization. These results are a step towards executing quantum approximate optimization at a scale that is not classically simulable. Reaching such system sizes is key to properly understanding the true potential of heuristic algorithms like QAOA.","lang":"eng"}],"file_date_updated":"2024-03-19T07:16:38Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","date_updated":"2026-10-16T12:12:26Z","DOAJ_listed":"1","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"fulldoi":"https://doi.org/10.1103/PhysRevResearch.6.013223","article_type":"original","has_accepted_license":"1","date_published":"2024-03-01T00:00:00Z","ddc":["530"],"publisher":"American Physical Society","year":"2024","citation":{"short":"S. Sack, D.J. Egger, Physical Review Research 6 (2024).","mla":"Sack, Stefan, and Daniel J. Egger. “Large-Scale Quantum Approximate Optimization on Nonplanar Graphs with Machine Learning Noise Mitigation.” <i>Physical Review Research</i>, vol. 6, no. 1, 013223, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PhysRevResearch.6.013223\">10.1103/PhysRevResearch.6.013223</a>.","chicago":"Sack, Stefan, and Daniel J. Egger. “Large-Scale Quantum Approximate Optimization on Nonplanar Graphs with Machine Learning Noise Mitigation.” <i>Physical Review Research</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PhysRevResearch.6.013223\">https://doi.org/10.1103/PhysRevResearch.6.013223</a>.","ieee":"S. Sack and D. J. Egger, “Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation,” <i>Physical Review Research</i>, vol. 6, no. 1. American Physical Society, 2024.","apa":"Sack, S., &#38; Egger, D. J. (2024). Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation. <i>Physical Review Research</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevResearch.6.013223\">https://doi.org/10.1103/PhysRevResearch.6.013223</a>","ista":"Sack S, Egger DJ. 2024. Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation. Physical Review Research. 6(1), 013223.","ama":"Sack S, Egger DJ. Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation. <i>Physical Review Research</i>. 2024;6(1). doi:<a href=\"https://doi.org/10.1103/PhysRevResearch.6.013223\">10.1103/PhysRevResearch.6.013223</a>"},"acknowledgement":"S.H.S. acknowledges support from the IBM Ph.D. fellowship 2022 in quantum computing. The authors also thank M. Serbyn, R. Kueng, R. A. Medina, and S. Woerner for fruitful discussions.","das_tickbox":"0","arxiv":1,"day":"01","oa_version":"Published Version","_id":"15122","status":"public","researchdata_availability":"no","intvolume":"         6","file":[{"file_name":"2024_PhysicalReviewResearch_Sack.pdf","date_created":"2024-03-19T07:16:38Z","file_size":2777593,"file_id":"15123","success":1,"content_type":"application/pdf","date_updated":"2024-03-19T07:16:38Z","creator":"dernst","relation":"main_file","checksum":"274c9f1b15b3547a10a03f39e4ccc582","access_level":"open_access"}],"issue":"1","external_id":{"arxiv":["2307.14427"]},"author":[{"orcid":"0000-0001-5400-8508","first_name":"Stefan","full_name":"Sack, Stefan","id":"dd622248-f6e0-11ea-865d-ce382a1c81a5","last_name":"Sack"},{"first_name":"Daniel J.","last_name":"Egger","full_name":"Egger, Daniel J."}],"publication":"Physical Review Research","scopus_import":"1","corr_author":"1","article_number":"013223","type":"journal_article","doi":"10.1103/PhysRevResearch.6.013223","title":"Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation","oa":1,"publication_identifier":{"eissn":["2643-1564"]},"month":"03","publication_status":"published","volume":6,"department":[{"_id":"MaSe"}],"language":[{"iso":"eng"}],"quality_controlled":"1","project":[{"name":"IBM PhD Nomination Fellowship - Stefan Sack","_id":"bd660c93-d553-11ed-ba76-fb0fb6f49c0d"}],"article_processing_charge":"Yes","supplementarymaterial":"yes","date_created":"2024-03-17T23:00:59Z"},{"issue":"10","external_id":{"arxiv":["2405.02102"],"isi":["001361617100003"]},"intvolume":"       110","_id":"18110","researchdata_availability":"no","status":"public","oa_version":"Preprint","isi":1,"day":"11","arxiv":1,"das_tickbox":"0","publisher":"American Physical Society","citation":{"mla":"Brighi, Pietro, and Marko Ljubotina. “Anomalous Transport in the Kinetically Constrained Quantum East-West Model.” <i>Physical Review B</i>, vol. 110, no. 10, L100304, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PhysRevB.110.L100304\">10.1103/PhysRevB.110.L100304</a>.","short":"P. Brighi, M. Ljubotina, Physical Review B 110 (2024).","chicago":"Brighi, Pietro, and Marko Ljubotina. “Anomalous Transport in the Kinetically Constrained Quantum East-West Model.” <i>Physical Review B</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PhysRevB.110.L100304\">https://doi.org/10.1103/PhysRevB.110.L100304</a>.","apa":"Brighi, P., &#38; Ljubotina, M. (2024). Anomalous transport in the kinetically constrained quantum East-West model. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevB.110.L100304\">https://doi.org/10.1103/PhysRevB.110.L100304</a>","ieee":"P. Brighi and M. Ljubotina, “Anomalous transport in the kinetically constrained quantum East-West model,” <i>Physical Review B</i>, vol. 110, no. 10. American Physical Society, 2024.","ama":"Brighi P, Ljubotina M. Anomalous transport in the kinetically constrained quantum East-West model. <i>Physical Review B</i>. 2024;110(10). doi:<a href=\"https://doi.org/10.1103/PhysRevB.110.L100304\">10.1103/PhysRevB.110.L100304</a>","ista":"Brighi P, Ljubotina M. 2024. Anomalous transport in the kinetically constrained quantum East-West model. Physical Review B. 110(10), L100304."},"year":"2024","acknowledgement":"The authors acknowledge useful discussions with M. Serbyn, Z. Papic, and A. Nunnenkamp. ´\r\nP.B. is supported by the Erwin Schrödinger Center for Quantum Science & Technology (ESQ) of the Österreichische Akademie der Wissenschaften (ÖAW) under the Discovery Grant. M.L. acknowledges support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement\r\nNo. 850899). The numerical simulations were performed using the ITensor library [68] on the Vienna Scientific Cluster (VSC).","date_published":"2024-09-11T00:00:00Z","article_type":"letter_note","fulldoi":"https://doi.org/10.1103/PhysRevB.110.L100304","date_updated":"2026-10-16T12:12:47Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ec_funded":1,"abstract":[{"lang":"eng","text":"We study a chaotic particle-conserving kinetically constrained model, with a single parameter which allows us to break reflection symmetry. Through extensive numerical simulations we find that the domain wall state shows a variety of dynamical behaviors from localization all the way to ballistic transport, depending on the value of the reflection breaking parameter. Surprisingly, such anomalous behavior is not mirrored in infinite-temperature dynamics, which appear to scale diffusively, in line with expectations for generic interacting models. However, studying the particle density gradient, we show that the lack of reflection symmetry affects infinite-temperature dynamics, resulting in an asymmetric dynamical structure factor. This is in disagreement with normal diffusion and suggests that the model may also exhibit anomalous dynamics at infinite temperature in the thermodynamic limit. Finally, we observe low-entangled eigenstates in the spectrum of the model, a telltale sign of quantum many-body scars."}],"article_processing_charge":"No","supplementarymaterial":"no","date_created":"2024-09-22T22:01:42Z","project":[{"call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","grant_number":"850899"}],"quality_controlled":"1","publication_status":"published","language":[{"iso":"eng"}],"volume":110,"department":[{"_id":"MaSe"}],"month":"09","oa":1,"title":"Anomalous transport in the kinetically constrained quantum East-West model","publication_identifier":{"issn":["2469-9950"],"eissn":["2469-9969"]},"type":"journal_article","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2405.02102","open_access":"1"}],"doi":"10.1103/PhysRevB.110.L100304","article_number":"L100304","corr_author":"1","scopus_import":"1","publication":"Physical Review B","author":[{"id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","last_name":"Brighi","full_name":"Brighi, Pietro","first_name":"Pietro","orcid":"0000-0002-7969-2729"},{"orcid":"0000-0003-0038-7068","first_name":"Marko","last_name":"Ljubotina","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","full_name":"Ljubotina, Marko"}]},{"date_created":"2024-02-18T23:01:00Z","supplementarymaterial":"yes","article_processing_charge":"No","quality_controlled":"1","language":[{"iso":"eng"}],"volume":132,"department":[{"_id":"MaSe"}],"publication_status":"published","month":"01","doi":"10.1103/PhysRevLett.132.050401","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2201.10220","open_access":"1"}],"type":"journal_article","publication_identifier":{"issn":["0031-9007"],"eissn":["1079-7114"]},"pmid":1,"oa":1,"title":"Fractal states of the Schwinger model","article_number":"050401","scopus_import":"1","author":[{"first_name":"Elena","id":"0ac84990-897b-11ed-a09c-f5abb56a4ede","last_name":"Petrova","full_name":"Petrova, Elena"},{"last_name":"Tiunov","full_name":"Tiunov, Egor S.","first_name":"Egor S."},{"last_name":"Bañuls","full_name":"Bañuls, Mari Carmen","first_name":"Mari Carmen"},{"first_name":"Aleksey K.","last_name":"Fedorov","full_name":"Fedorov, Aleksey K."}],"publication":"Physical Review Letters","intvolume":"       132","external_id":{"pmid":["38364163"],"arxiv":["2201.10220"],"isi":["001179276700003"]},"issue":"5","oa_version":"Preprint","_id":"15002","status":"public","researchdata_availability":"no","acknowledgement":"We thank A. Bargov, I. Khaymovich, and V. Tiunova for fruitful discussions and for useful comments. M. C. B. thanks S. Kühn for discussions about the phase structure of the model. A. K. F. thanks V. Gritsev and A. Garkun for insightful comments. E. V. P., E. S. T., and A. K. F. are\r\nsupported by the RSF Grant No. 20-42-05002 (studying the fractal Ansatz) and the Roadmap on Quantum Computing (Contract No. 868-1.3-15/15-2021, October 5, 2021; calculating on GS energies). A. K. F. thanks the Priority 2030 program at the NIST “MISIS” under the project No. K1-2022-027. M. C. B. was partly funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC-2111–390814868.","citation":{"chicago":"Petrova, Elena, Egor S. Tiunov, Mari Carmen Bañuls, and Aleksey K. Fedorov. “Fractal States of the Schwinger Model.” <i>Physical Review Letters</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PhysRevLett.132.050401\">https://doi.org/10.1103/PhysRevLett.132.050401</a>.","mla":"Petrova, Elena, et al. “Fractal States of the Schwinger Model.” <i>Physical Review Letters</i>, vol. 132, no. 5, 050401, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PhysRevLett.132.050401\">10.1103/PhysRevLett.132.050401</a>.","short":"E. Petrova, E.S. Tiunov, M.C. Bañuls, A.K. Fedorov, Physical Review Letters 132 (2024).","ista":"Petrova E, Tiunov ES, Bañuls MC, Fedorov AK. 2024. Fractal states of the Schwinger model. Physical Review Letters. 132(5), 050401.","ama":"Petrova E, Tiunov ES, Bañuls MC, Fedorov AK. Fractal states of the Schwinger model. <i>Physical Review Letters</i>. 2024;132(5). doi:<a href=\"https://doi.org/10.1103/PhysRevLett.132.050401\">10.1103/PhysRevLett.132.050401</a>","ieee":"E. Petrova, E. S. Tiunov, M. C. Bañuls, and A. K. Fedorov, “Fractal states of the Schwinger model,” <i>Physical Review Letters</i>, vol. 132, no. 5. American Physical Society, 2024.","apa":"Petrova, E., Tiunov, E. S., Bañuls, M. C., &#38; Fedorov, A. K. (2024). Fractal states of the Schwinger model. <i>Physical Review Letters</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevLett.132.050401\">https://doi.org/10.1103/PhysRevLett.132.050401</a>"},"year":"2024","publisher":"American Physical Society","arxiv":1,"das_tickbox":"0","day":"30","isi":1,"fulldoi":"https://doi.org/10.1103/PhysRevLett.132.050401","article_type":"original","date_published":"2024-01-30T00:00:00Z","date_updated":"2026-10-16T12:12:00Z","abstract":[{"lang":"eng","text":"The lattice Schwinger model, the discrete version of QED in \r\n1\r\n+\r\n1\r\n dimensions, is a well-studied test bench for lattice gauge theories. Here, we study the fractal properties of this model. We reveal the self-similarity of the ground state, which allows us to develop a recurrent procedure for finding the ground-state wave functions and predicting ground-state energies. We present the results of recurrently calculating ground-state wave functions using the fractal Ansatz and automized software package for fractal image processing. In certain parameter regimes, just a few terms are enough for our recurrent procedure to predict ground-state energies close to the exact ones for several hundreds of sites. Our findings pave the way to understanding the complexity of calculating many-body wave functions in terms of their fractal properties as well as finding new links between condensed matter and high-energy lattice models."}],"user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345"},{"article_processing_charge":"No","supplementarymaterial":"no","date_created":"2024-07-09T09:14:24Z","related_material":{"record":[{"relation":"part_of_dissertation","id":"10545","status":"public"},{"id":"10067","relation":"part_of_dissertation","status":"public"},{"id":"13125","relation":"part_of_dissertation","status":"public"},{"status":"public","relation":"part_of_dissertation","id":"11471"},{"relation":"part_of_dissertation","id":"17222","status":"public"}]},"project":[{"grant_number":"850899","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","call_identifier":"H2020"}],"degree_awarded":"PhD","publication_status":"published","language":[{"iso":"eng"}],"department":[{"_id":"GradSch"},{"_id":"MaSe"}],"page":"133","month":"07","type":"dissertation","doi":"10.15479/at:ista:17208","oa":1,"title":"Exploring the optimization landscape of variational quantum algorithms","publication_identifier":{"issn":["2663-337X"]},"doi_confirm":"1","corr_author":"1","author":[{"orcid":"0000-0002-5383-2869","first_name":"Raimel A","id":"CE680B90-D85A-11E9-B684-C920E6697425","last_name":"Medina Ramos","full_name":"Medina Ramos, Raimel A"}],"acknowledged_ssus":[{"_id":"ScienComp"}],"file":[{"file_id":"17212","file_size":"14218691","date_created":"2024-07-09T09:21:44Z","file_name":"Raimel_Thesis-Final.zip","relation":"source_file","access_level":"closed","checksum":"6f45273d04f4418bc2adc018baed0525","creator":"rmedinar","content_type":"application/zip","date_updated":"2024-07-10T11:34:09Z"},{"success":1,"file_id":"17275","file_name":"Raimel_Thesis-20_pdfa.pdf","date_created":"2024-07-17T09:23:24Z","file_size":11253627,"checksum":"6724a95bec772dbabc0111b9f08a805e","access_level":"open_access","relation":"main_file","date_updated":"2024-07-17T09:23:24Z","content_type":"application/pdf","creator":"rmedinar"}],"oa_version":"Published Version","researchdata_availability":"no","_id":"17208","status":"public","publisher":"Institute of Science and Technology Austria","year":"2024","citation":{"short":"R.A. Medina Ramos, Exploring the Optimization Landscape of Variational Quantum Algorithms, Institute of Science and Technology Austria, 2024.","mla":"Medina Ramos, Raimel A. <i>Exploring the Optimization Landscape of Variational Quantum Algorithms</i>. Institute of Science and Technology Austria, 2024, doi:<a href=\"https://doi.org/10.15479/at:ista:17208\">10.15479/at:ista:17208</a>.","chicago":"Medina Ramos, Raimel A. “Exploring the Optimization Landscape of Variational Quantum Algorithms.” Institute of Science and Technology Austria, 2024. <a href=\"https://doi.org/10.15479/at:ista:17208\">https://doi.org/10.15479/at:ista:17208</a>.","ieee":"R. A. Medina Ramos, “Exploring the optimization landscape of variational quantum algorithms,” Institute of Science and Technology Austria, 2024.","apa":"Medina Ramos, R. A. (2024). <i>Exploring the optimization landscape of variational quantum algorithms</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:17208\">https://doi.org/10.15479/at:ista:17208</a>","ista":"Medina Ramos RA. 2024. Exploring the optimization landscape of variational quantum algorithms. Institute of Science and Technology Austria.","ama":"Medina Ramos RA. Exploring the optimization landscape of variational quantum algorithms. 2024. doi:<a href=\"https://doi.org/10.15479/at:ista:17208\">10.15479/at:ista:17208</a>"},"supervisor":[{"orcid":"0000-0002-2399-5827","first_name":"Maksym","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","last_name":"Serbyn","full_name":"Serbyn, Maksym"}],"das_tickbox":"0","day":"09","keyword":["Quantum computing","Variational Quantum Algorithms","Optimization"],"tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"fulldoi":"https://doi.org/10.15479/at:ista:17208","has_accepted_license":"1","date_published":"2024-07-09T00:00:00Z","ddc":["539"],"OA_place":"publisher","date_updated":"2026-10-16T12:14:52Z","alternative_title":["ISTA Thesis"],"ec_funded":1,"abstract":[{"lang":"eng","text":"Can current quantum computers provide a speedup over their classical counterparts for some kinds of problems? In this thesis, with a focus on ground state search/preparation, we address some of the challenges that both quantum annealing and variational quantum algorithms suffer from, hindering any possible practical speedup in comparison to the best classical counterparts. \r\n\r\nIn the first part of the thesis, we study the performance of quantum annealing for solving a particular combinatorial optimization problem called 3-XOR satisfability (3-XORSAT). The classical problem is mapped into a ground state search of a 3-local classical Hamiltonian $H_C$. We consider how modifying the initial problem, by adding more interaction terms to the corresponding Hamiltonian, leads to the emergence of a first-order phase transition during the annealing process. This phenomenon causes the total annealing duration, $T$, required to prepare the ground state of $H_C$ with a high probability to increase exponentially with the size of the problem. Our findings indicate that with the growing complexity of problem instances, the likelihood of encountering first-order phase transitions also increases, making quantum annealing an impractical solution for these types of combinatorial optimization problems.\r\n\r\nIn the second part, we focus on the problem of barren plateaus in generic variational quantum algorithms. Barren plateaus correspond to flat regions in the parameter space where the gradient of the cost function is zero in expectation, and with the variance decaying exponentially with the system size, thus obstructing an efficient parameter optimization.  We propose an algorithm to circumvent Barren Plateaus by monitoring the entanglement entropy of k-local reduced density matrices, alongside a method for estimating entanglement entropy via classical shadow tomography. We illustrate the approach with the paradigmatic example of the variational quantum eigensolver, and show that our algorithm effectively avoids barren plateaus in the initialization as well as during the optimization stage. \r\n\r\nLastly, in the last two Chapters of this thesis, we focus on the quantum approximate optimization algorithm (QAOA), originally introduced as an algorithm for solving generic combinatorial optimization problems in near-term quantum devices. Specifically, we focus on how to develop rigorous initialization strategies with guarantee improvement. Our motivation for this study lies in that for random initialization, the optimization typically leads to local minima with poor performance. Our main result corresponds to the analytical construction of index-1 saddle points or transition states, stationary points with a single direction of descent, as a tool for systematically exploring the QAOA optimization landscape. This leads us to propose a novel greedy parameter initialization strategy that guarantees for the energy to decrease with an increasing number of circuit layers. Furthermore, with precise estimates for the negative Hessian eigenvalue and its eigenvector, we establish a lower bound for energy improvement following a QAOA iteration."}],"file_date_updated":"2024-07-17T09:23:24Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345"},{"external_id":{"isi":["001299667100002"],"arxiv":["2311.08108"]},"issue":"3","file":[{"success":1,"file_id":"17532","file_name":"2024_PhysRevX_Vermersch.pdf","date_created":"2024-09-05T09:39:00Z","file_size":1408836,"checksum":"1b114acc89025120727200681e4e9074","access_level":"open_access","relation":"main_file","date_updated":"2024-09-05T09:39:00Z","content_type":"application/pdf","creator":"cchlebak"}],"intvolume":"        14","arxiv":1,"das_tickbox":"0","day":"26","isi":1,"acknowledgement":"B. V. acknowledges funding from the Austrian Science Foundation (Grant No. FWF, P 32597 N), from the French National Research Agency via the JCJC project QRand (Grant No. ANR-20-CE47-0005), and via the research programs Plan France 2030 EPIQ (Grant No. ANR-22-PETQ-0007), QUBITAF (Grant No. ANR-22-PETQ-0004), and HQI (Grant No. ANR-22-PNCQ-0002). M. L. and M. S. acknowledge support by the European Research Council under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899). M. S. acknowledges the hospitality of KITP supported in part by the National Science Foundation under Grants No. NSF PHY-1748958 and No. NSF PHY-2309135. J. I. C. is supported by the Hightech Agenda Bayern Plus through the Munich Quantum Valley and the German Federal Ministry of Education and Research through EQUAHUMO (Grant No. 13N16066). P. Z. acknowledges funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 101113690 (PASQuanS2.1).","citation":{"ama":"Vermersch B, Ljubotina M, Cirac JI, Zoller P, Serbyn M, Piroli L. Many-body entropies and entanglement from polynomially many local measurements. <i>Physical Review X</i>. 2024;14(3). doi:<a href=\"https://doi.org/10.1103/physrevx.14.031035\">10.1103/physrevx.14.031035</a>","ista":"Vermersch B, Ljubotina M, Cirac JI, Zoller P, Serbyn M, Piroli L. 2024. Many-body entropies and entanglement from polynomially many local measurements. Physical Review X. 14(3), 031035.","apa":"Vermersch, B., Ljubotina, M., Cirac, J. I., Zoller, P., Serbyn, M., &#38; Piroli, L. (2024). Many-body entropies and entanglement from polynomially many local measurements. <i>Physical Review X</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevx.14.031035\">https://doi.org/10.1103/physrevx.14.031035</a>","ieee":"B. Vermersch, M. Ljubotina, J. I. Cirac, P. Zoller, M. Serbyn, and L. Piroli, “Many-body entropies and entanglement from polynomially many local measurements,” <i>Physical Review X</i>, vol. 14, no. 3. American Physical Society, 2024.","chicago":"Vermersch, Benoît, Marko Ljubotina, J. Ignacio Cirac, Peter Zoller, Maksym Serbyn, and Lorenzo Piroli. “Many-Body Entropies and Entanglement from Polynomially Many Local Measurements.” <i>Physical Review X</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/physrevx.14.031035\">https://doi.org/10.1103/physrevx.14.031035</a>.","short":"B. Vermersch, M. Ljubotina, J.I. Cirac, P. Zoller, M. Serbyn, L. Piroli, Physical Review X 14 (2024).","mla":"Vermersch, Benoît, et al. “Many-Body Entropies and Entanglement from Polynomially Many Local Measurements.” <i>Physical Review X</i>, vol. 14, no. 3, 031035, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/physrevx.14.031035\">10.1103/physrevx.14.031035</a>."},"year":"2024","publisher":"American Physical Society","_id":"17493","researchdata_availability":"no","status":"public","oa_version":"Published Version","OA_place":"publisher","DOAJ_listed":"1","ddc":["530"],"has_accepted_license":"1","OA_type":"gold","date_published":"2024-08-26T00:00:00Z","article_type":"original","fulldoi":"https://doi.org/10.1103/physrevx.14.031035","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ec_funded":1,"abstract":[{"text":"Estimating global properties of many-body quantum systems such as entropy or bipartite entanglement is a notoriously difficult task, typically requiring a number of measurements or classical postprocessing resources growing exponentially in the system size. In this work, we address the problem of estimating global entropies and mixed-state entanglement via partial-transposed (PT) moments and show that efficient estimation strategies exist under the assumption that all the spatial correlation lengths are finite. Focusing on one-dimensional systems, we identify a set of approximate factorization conditions (AFCs) on the system density matrix, which allow us to reconstruct entropies and PT moments from information on local subsystems. This identification yields a simple and efficient strategy for entropy and entanglement estimation. Our method could be implemented in different ways, depending on how information on local subsystems is extracted. Focusing on randomized measurements providing a practical and common measurement scheme, we prove that our protocol requires only polynomially many measurements and postprocessing operations, assuming that the state to be measured satisfies the AFCs. We prove that the AFCs hold for finite-depth quantum-circuit states and translation-invariant matrix-product density operators and provide numerical evidence that they are satisfied in more general, physically interesting cases, including thermal states of local Hamiltonians. We argue that our method could be practically useful to detect bipartite mixed-state entanglement for large numbers of qubits available in today’s quantum platforms.","lang":"eng"}],"file_date_updated":"2024-09-05T09:39:00Z","date_updated":"2026-10-16T12:15:28Z","project":[{"call_identifier":"H2020","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","grant_number":"850899"}],"quality_controlled":"1","date_created":"2024-09-04T18:57:11Z","supplementarymaterial":"yes","APC_amount":"4863,6 EUR","article_processing_charge":"Yes","month":"08","department":[{"_id":"MaSe"}],"language":[{"iso":"eng"}],"volume":14,"publication_status":"published","article_number":"031035","publication_identifier":{"issn":["2160-3308"]},"oa":1,"title":"Many-body entropies and entanglement from polynomially many local measurements","doi":"10.1103/physrevx.14.031035","type":"journal_article","publication":"Physical Review X","author":[{"first_name":"Benoît","last_name":"Vermersch","full_name":"Vermersch, Benoît"},{"full_name":"Ljubotina, Marko","last_name":"Ljubotina","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","orcid":"0000-0003-0038-7068","first_name":"Marko"},{"first_name":"J. Ignacio","full_name":"Cirac, J. Ignacio","last_name":"Cirac"},{"first_name":"Peter","full_name":"Zoller, Peter","last_name":"Zoller"},{"last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","orcid":"0000-0002-2399-5827","first_name":"Maksym"},{"first_name":"Lorenzo","last_name":"Piroli","full_name":"Piroli, Lorenzo"}],"scopus_import":"1"},{"has_accepted_license":"1","date_published":"2024-05-01T00:00:00Z","ddc":["530"],"tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"article_type":"original","fulldoi":"https://doi.org/10.21468/scipostphys.16.5.115","date_updated":"2026-10-16T12:15:53Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","file_date_updated":"2024-05-07T12:58:47Z","abstract":[{"text":"Two-dimensional semiconductor-superconductor heterostructures form the foundation of numerous nanoscale physical systems. However, measuring the properties of such heterostructures, and characterizing the semiconductor in-situ is challenging. A recent experimental study by [Phys. Rev. Lett. 128, 107701 (2022)] was able to probe the semiconductor within the heterostructure using microwave measurements of the superfluid density. This work revealed a rapid depletion of superfluid density in semiconductor, caused by the in-plane magnetic field which in presence of spin-orbit coupling creates so-called Bogoliubov Fermi surfaces. The experimental work used a simplified theoretical model that neglected the presence of non-magnetic disorder in the semiconductor, hence describing the data only qualitatively. Motivated by experiments, we introduce a theoretical model describing a disordered semiconductor with strong spin-orbit coupling that is proximitized by a superconductor. Our model provides specific predictions for the density of states and superfluid density. Presence of disorder leads to the emergence of a gapless superconducting phase, that may be viewed as a manifestation of Bogoliubov Fermi surface. When applied to real experimental data, our model showcases excellent quantitative agreement, enabling the extraction of material parameters such as mean free path and mobility, and estimating g-tensor after taking into account the orbital contribution of magnetic field. Our model can be used to probe in-situ parameters of other superconductor-semiconductor heterostructures and can be further extended to give access to transport properties.","lang":"eng"}],"issue":"5","external_id":{"arxiv":["2311.09347"],"isi":["001215855200002"]},"intvolume":"        16","file":[{"creator":"dernst","content_type":"application/pdf","date_updated":"2024-05-07T12:58:47Z","relation":"main_file","access_level":"open_access","checksum":"f999204856417dcf5a736ac8df432b96","file_size":2733685,"date_created":"2024-05-07T12:58:47Z","file_name":"2024_SciPostPhys_Babkin.pdf","file_id":"15369","success":1}],"researchdata_availability":"no","_id":"15367","status":"public","oa_version":"Published Version","isi":1,"day":"01","das_tickbox":"0","arxiv":1,"publisher":"SciPost Foundation","acknowledgement":"We acknowledge useful discussions with M. Geier, A. Levchenko, B. Ramshaw, T. Scaffidi, and\r\nJ. Shabani. This research was funded by the Austrian Science Fund (FWF) F 86.\r\nFor the purpose of open access, authors have applied a CC BY public copyright licence to any\r\nAuthor Accepted Manuscript version arising from this submission. MS acknowledges hospitality of KITP supported in part by the National Science Foundation under Grants No. NSF\r\nPHY-1748958 and PHY-2309135. APH acknowledges the support of the NOMIS foundation.","year":"2024","citation":{"mla":"Babkin, Serafim, et al. “Proximity-Induced Gapless Superconductivity in Two-Dimensional Rashba Semiconductor in Magnetic Field.” <i>SciPost Physics</i>, vol. 16, no. 5, 115, SciPost Foundation, 2024, doi:<a href=\"https://doi.org/10.21468/scipostphys.16.5.115\">10.21468/scipostphys.16.5.115</a>.","short":"S. Babkin, A.P. Higginbotham, M. Serbyn, SciPost Physics 16 (2024).","chicago":"Babkin, Serafim, Andrew P Higginbotham, and Maksym Serbyn. “Proximity-Induced Gapless Superconductivity in Two-Dimensional Rashba Semiconductor in Magnetic Field.” <i>SciPost Physics</i>. SciPost Foundation, 2024. <a href=\"https://doi.org/10.21468/scipostphys.16.5.115\">https://doi.org/10.21468/scipostphys.16.5.115</a>.","apa":"Babkin, S., Higginbotham, A. P., &#38; Serbyn, M. (2024). Proximity-induced gapless superconductivity in two-dimensional Rashba semiconductor in magnetic field. <i>SciPost Physics</i>. SciPost Foundation. <a href=\"https://doi.org/10.21468/scipostphys.16.5.115\">https://doi.org/10.21468/scipostphys.16.5.115</a>","ieee":"S. Babkin, A. P. Higginbotham, and M. Serbyn, “Proximity-induced gapless superconductivity in two-dimensional Rashba semiconductor in magnetic field,” <i>SciPost Physics</i>, vol. 16, no. 5. SciPost Foundation, 2024.","ama":"Babkin S, Higginbotham AP, Serbyn M. Proximity-induced gapless superconductivity in two-dimensional Rashba semiconductor in magnetic field. <i>SciPost Physics</i>. 2024;16(5). doi:<a href=\"https://doi.org/10.21468/scipostphys.16.5.115\">10.21468/scipostphys.16.5.115</a>","ista":"Babkin S, Higginbotham AP, Serbyn M. 2024. Proximity-induced gapless superconductivity in two-dimensional Rashba semiconductor in magnetic field. SciPost Physics. 16(5), 115."},"title":"Proximity-induced gapless superconductivity in two-dimensional Rashba semiconductor in magnetic field","oa":1,"publication_identifier":{"issn":["2542-4653"]},"type":"journal_article","doi":"10.21468/scipostphys.16.5.115","article_number":"115","corr_author":"1","scopus_import":"1","publication":"SciPost Physics","author":[{"orcid":"0009-0003-7382-8036","first_name":"Serafim","full_name":"Babkin, Serafim","last_name":"Babkin","id":"41e64307-6672-11ee-b9ad-cc7a0075a479"},{"orcid":"0000-0003-2607-2363","first_name":"Andrew P","last_name":"Higginbotham","id":"4AD6785A-F248-11E8-B48F-1D18A9856A87","full_name":"Higginbotham, Andrew P"},{"first_name":"Maksym","orcid":"0000-0002-2399-5827","last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym"}],"article_processing_charge":"Yes","date_created":"2024-05-06T09:02:18Z","supplementarymaterial":"no","project":[{"_id":"eb9b30ac-77a9-11ec-83b8-871f581d53d2","name":"Protected states of quantum matter"},{"_id":"34a7f947-11ca-11ed-8bc3-c5dc2bbaae25","name":"Center for Correlated Quantum Materials and Solid State Quantum Systems:  Probing topology in circuits and quantum materials","grant_number":"F8609"}],"quality_controlled":"1","publication_status":"published","department":[{"_id":"MaSe"},{"_id":"AnHi"}],"language":[{"iso":"eng"}],"volume":16,"month":"05"},{"supplementarymaterial":"yes","date_created":"2024-12-08T23:01:55Z","article_processing_charge":"No","project":[{"grant_number":"101034413","call_identifier":"H2020","_id":"fc2ed2f7-9c52-11eb-aca3-c01059dda49c","name":"IST-BRIDGE: International postdoctoral program"}],"quality_controlled":"1","related_material":{"record":[{"id":"17471","relation":"research_data","status":"public"}]},"department":[{"_id":"MaSe"}],"volume":133,"language":[{"iso":"eng"}],"publication_status":"published","month":"11","publication_identifier":{"eissn":["1079-7114"],"issn":["0031-9007"]},"pmid":1,"oa":1,"title":"Enhanced many-body quantum scars from the non-hermitian fock skin effect","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2403.02395","open_access":"1"}],"doi":"10.1103/PhysRevLett.133.216601","type":"journal_article","article_number":"216601","scopus_import":"1","publication":"Physical Review Letters","author":[{"last_name":"Shen","full_name":"Shen, Ruizhe","first_name":"Ruizhe"},{"full_name":"Qin, Fang","last_name":"Qin","first_name":"Fang"},{"id":"6c292945-a610-11ed-9eec-c3be1ad62a80","last_name":"Desaules","full_name":"Desaules, Jean-Yves Marc","orcid":"0000-0002-3749-6375","first_name":"Jean-Yves Marc"},{"last_name":"Papić","full_name":"Papić, Zlatko","first_name":"Zlatko"},{"full_name":"Lee, Ching Hua","last_name":"Lee","first_name":"Ching Hua"}],"dataavailabilitystatement":"The data supporting the plots within this paper are available at 10.15479/AT:ISTA:17471","external_id":{"isi":["001369697800005"],"arxiv":["2403.02395"],"pmid":["39642519"]},"issue":"21","intvolume":"       133","status":"public","_id":"18627","researchdata_availability":"yes","oa_version":"Preprint","day":"22","arxiv":1,"das_tickbox":"1","isi":1,"acknowledgement":"F. Q. and C. H. L. acknowledge support from the QEP2.0 Grant from the Singapore National Research Foundation (Grant No. NRF2021-QEP2-02-P09) and the Singapore MOE Tier-II Grant (Grant No. MOE-T2EP50222-0003). J.-Y. D. and Z. P. acknowledge support by the Leverhulme Trust Research Leadership Award RL-2019-015. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 101034413. This research was supported in part by Grant No. NSF PHY-2309135 to the Kavli Institute for Theoretical Physics (KITP). We acknowledge the use of IBM Quantum services for this work. The views expressed are those of the authors and do not reflect the official policy or position of IBM or the IBM Quantum team.","year":"2024","citation":{"chicago":"Shen, Ruizhe, Fang Qin, Jean-Yves Marc Desaules, Zlatko Papić, and Ching Hua Lee. “Enhanced Many-Body Quantum Scars from the Non-Hermitian Fock Skin Effect.” <i>Physical Review Letters</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PhysRevLett.133.216601\">https://doi.org/10.1103/PhysRevLett.133.216601</a>.","short":"R. Shen, F. Qin, J.-Y.M. Desaules, Z. Papić, C.H. Lee, Physical Review Letters 133 (2024).","mla":"Shen, Ruizhe, et al. “Enhanced Many-Body Quantum Scars from the Non-Hermitian Fock Skin Effect.” <i>Physical Review Letters</i>, vol. 133, no. 21, 216601, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PhysRevLett.133.216601\">10.1103/PhysRevLett.133.216601</a>.","ama":"Shen R, Qin F, Desaules J-YM, Papić Z, Lee CH. Enhanced many-body quantum scars from the non-hermitian fock skin effect. <i>Physical Review Letters</i>. 2024;133(21). doi:<a href=\"https://doi.org/10.1103/PhysRevLett.133.216601\">10.1103/PhysRevLett.133.216601</a>","ista":"Shen R, Qin F, Desaules J-YM, Papić Z, Lee CH. 2024. Enhanced many-body quantum scars from the non-hermitian fock skin effect. Physical Review Letters. 133(21), 216601.","apa":"Shen, R., Qin, F., Desaules, J.-Y. M., Papić, Z., &#38; Lee, C. H. (2024). Enhanced many-body quantum scars from the non-hermitian fock skin effect. <i>Physical Review Letters</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevLett.133.216601\">https://doi.org/10.1103/PhysRevLett.133.216601</a>","ieee":"R. Shen, F. Qin, J.-Y. M. Desaules, Z. Papić, and C. H. Lee, “Enhanced many-body quantum scars from the non-hermitian fock skin effect,” <i>Physical Review Letters</i>, vol. 133, no. 21. American Physical Society, 2024."},"publisher":"American Physical Society","OA_type":"green","date_published":"2024-11-22T00:00:00Z","article_type":"original","fulldoi":"https://doi.org/10.1103/PhysRevLett.133.216601","OA_place":"repository","date_updated":"2026-10-16T12:14:03Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ec_funded":1,"abstract":[{"lang":"eng","text":"In contrast with extended Bloch waves, a single particle can become spatially localized due to the so-called skin effect originating from non-Hermitian pumping. Here we show that in kinetically constrained many-body systems, the skin effect can instead manifest as dynamical amplification within the Fock space, beyond the intuitively expected and previously studied particle localization and clustering. We exemplify this non-Hermitian Fock skin effect in an asymmetric version of the PXP model and show that it gives rise to ergodicity-breaking eigenstates—the non-Hermitian analogs of quantum many-body scars. A distinguishing feature of these non-Hermitian scars is their enhanced robustness against external disorders. We propose an experimental realization of the non-Hermitian scar enhancement in a tilted Bose-Hubbard optical lattice with laser-induced loss. Additionally, we implement digital simulations of such scar enhancement on the IBM quantum processor. Our results show that the Fock skin effect provides a powerful tool for creating robust nonergodic states in generic open quantum systems."}]},{"user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","file_date_updated":"2025-01-27T15:03:09Z","abstract":[{"lang":"eng","text":"Combinatorial optimization is a challenging problem applicable in a wide range of fields from logistics to finance. Recently, quantum computing has been used to attempt to solve these problems using a range of algorithms, including parameterized quantum circuits, adiabatic protocols, and quantum annealing. These solutions typically have several challenges: 1) there is little to no performance gain over classical methods; 2) not all constraints and objectives may be efficiently encoded in the quantum ansatz; and 3) the solution domain of the objective function may not be the same as the bit strings of measurement outcomes. This work presents “nonnative hybrid algorithms”: a framework to overcome these challenges by integrating quantum and classical resources with a hybrid approach. By designing nonnative quantum variational anosatzes that inherit some but not all problem structure, measurement outcomes from the quantum computer can act as a resource to be used by classical routines to indirectly compute optimal solutions, partially overcoming the challenges of contemporary quantum optimization approaches. These methods are demonstrated using a publicly available neutral-atom quantum computer on two simple problems of Max k-Cut and maximum independent set. We find improvements in solution quality when comparing the hybrid algorithm to its “no quantum” version, a demonstration of a “comparative advantage.”"}],"date_updated":"2026-10-16T12:15:09Z","OA_place":"publisher","ddc":["530"],"date_published":"2024-08-14T00:00:00Z","OA_type":"hybrid","has_accepted_license":"1","article_type":"original","fulldoi":"https://doi.org/10.1109/tqe.2024.3443660","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"das_tickbox":"0","day":"14","acknowledgement":"The authors would like to thank Alexander Keesling, Maddie Cain, Nate Gemelke, and Phillip Weinberg for helpful discussions and Danylo Lykov who had early contributions to this work.\r\n10.13039/100000185-Defense Advanced Research Projects Agency Noisy Intermediate-Scale Quantum Devices (Grant Number: W911NF2010021), DARPA Small Business Technology Transfer program (Grant Number: 140D0422C0035).","year":"2024","citation":{"ista":"Wurtz J, Sack S, Wang S-T. 2024. Solving nonnative combinatorial optimization problems using hybrid quantum–classical algorithms. IEEE Transactions on Quantum Engineering. 5, 1–14.","ama":"Wurtz J, Sack S, Wang S-T. Solving nonnative combinatorial optimization problems using hybrid quantum–classical algorithms. <i>IEEE Transactions on Quantum Engineering</i>. 2024;5:1-14. doi:<a href=\"https://doi.org/10.1109/tqe.2024.3443660\">10.1109/tqe.2024.3443660</a>","apa":"Wurtz, J., Sack, S., &#38; Wang, S.-T. (2024). Solving nonnative combinatorial optimization problems using hybrid quantum–classical algorithms. <i>IEEE Transactions on Quantum Engineering</i>. IEEE. <a href=\"https://doi.org/10.1109/tqe.2024.3443660\">https://doi.org/10.1109/tqe.2024.3443660</a>","ieee":"J. Wurtz, S. Sack, and S.-T. Wang, “Solving nonnative combinatorial optimization problems using hybrid quantum–classical algorithms,” <i>IEEE Transactions on Quantum Engineering</i>, vol. 5. IEEE, pp. 1–14, 2024.","chicago":"Wurtz, Jonathan, Stefan Sack, and Sheng-Tao Wang. “Solving Nonnative Combinatorial Optimization Problems Using Hybrid Quantum–Classical Algorithms.” <i>IEEE Transactions on Quantum Engineering</i>. IEEE, 2024. <a href=\"https://doi.org/10.1109/tqe.2024.3443660\">https://doi.org/10.1109/tqe.2024.3443660</a>.","mla":"Wurtz, Jonathan, et al. “Solving Nonnative Combinatorial Optimization Problems Using Hybrid Quantum–Classical Algorithms.” <i>IEEE Transactions on Quantum Engineering</i>, vol. 5, IEEE, 2024, pp. 1–14, doi:<a href=\"https://doi.org/10.1109/tqe.2024.3443660\">10.1109/tqe.2024.3443660</a>.","short":"J. Wurtz, S. Sack, S.-T. Wang, IEEE Transactions on Quantum Engineering 5 (2024) 1–14."},"publisher":"IEEE","_id":"18923","researchdata_availability":"no","status":"public","oa_version":"Published Version","file":[{"relation":"main_file","checksum":"19b84e35cba05bde72bfe7e0b54c3e6c","access_level":"open_access","date_updated":"2025-01-27T15:03:09Z","content_type":"application/pdf","creator":"dernst","file_id":"18924","success":1,"file_name":"2024_IEEEQuantumComputing_Wurtz.pdf","file_size":1753095,"date_created":"2025-01-27T15:03:09Z"}],"intvolume":"         5","publication":"IEEE Transactions on Quantum Engineering","author":[{"first_name":"Jonathan","last_name":"Wurtz","full_name":"Wurtz, Jonathan"},{"orcid":"0000-0001-5400-8508","first_name":"Stefan","id":"dd622248-f6e0-11ea-865d-ce382a1c81a5","last_name":"Sack","full_name":"Sack, Stefan"},{"first_name":"Sheng-Tao","full_name":"Wang, Sheng-Tao","last_name":"Wang"}],"scopus_import":"1","publication_identifier":{"issn":["2689-1808"]},"title":"Solving nonnative combinatorial optimization problems using hybrid quantum–classical algorithms","oa":1,"doi":"10.1109/tqe.2024.3443660","type":"journal_article","month":"08","page":"1-14","department":[{"_id":"MaSe"}],"language":[{"iso":"eng"}],"volume":5,"publication_status":"published","quality_controlled":"1","supplementarymaterial":"no","date_created":"2025-01-27T15:00:44Z","article_processing_charge":"Yes (in subscription journal)"},{"date_updated":"2026-10-16T12:14:03Z","abstract":[{"lang":"eng","text":"Mechanisms for suppressing thermalization in disorder-free many-body systems, such as Hilbert space fragmentation and quantum many-body scars, have recently attracted much interest in foundations of quantum statistical physics and potential quantum information processing applications. However,  their sensitivity to realistic effects such as finite temperature remains largely unexplored. Here, we have utilized IBM's Kolkata quantum processor to demonstrate an unexpected robustness of quantum many-body scars at finite temperatures when the system is prepared in a thermal Gibbs ensemble. We identify such robustness in the PXP model, which describes quantum many-body scars in experimental systems of Rydberg atom arrays and ultracold atoms in tilted Bose--Hubbard optical lattices. By contrast, other theoretical models which host exact quantum many-body scars are found to lack such robustness, and their scarring properties quickly decay with temperature. Our study sheds light on the important differences between scarred models in terms of their algebraic structures, which impacts their resilience to finite temperature."}],"ec_funded":1,"file_date_updated":"2024-08-30T13:19:57Z","user_id":"68b8ca59-c5b3-11ee-8790-cd641c68093d","fulldoi":"https://doi.org/10.15479/AT:ISTA:17471","keyword":["quantum many-body scars","non-equilibrium physics","non-Hermitian physics"],"tmp":{"name":"Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)","short":"CC BY-NC (4.0)","legal_code_url":"https://creativecommons.org/licenses/by-nc/4.0/legalcode","image":"/images/cc_by_nc.png"},"ddc":["530"],"has_accepted_license":"1","date_published":"2024-08-30T00:00:00Z","oa_version":"Published Version","status":"public","_id":"17471","citation":{"short":"J.-Y.M. Desaules, (2024).","mla":"Desaules, Jean-Yves Marc. <i>Data for “Enhanced Many-Body Quantum Scars from the Non-Hermitian Fock Skin Effect.”</i> Institute of Science and Technology Austria, 2024, doi:<a href=\"https://doi.org/10.15479/AT:ISTA:17471\">10.15479/AT:ISTA:17471</a>.","chicago":"Desaules, Jean-Yves Marc. “Data for ‘Enhanced Many-Body Quantum Scars from the Non-Hermitian Fock Skin Effect.’” Institute of Science and Technology Austria, 2024. <a href=\"https://doi.org/10.15479/AT:ISTA:17471\">https://doi.org/10.15479/AT:ISTA:17471</a>.","ieee":"J.-Y. M. Desaules, “Data for ‘Enhanced many-body quantum scars from the non-Hermitian Fock skin effect.’” Institute of Science and Technology Austria, 2024.","apa":"Desaules, J.-Y. M. (2024). Data for “Enhanced many-body quantum scars from the non-Hermitian Fock skin effect.” Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/AT:ISTA:17471\">https://doi.org/10.15479/AT:ISTA:17471</a>","ama":"Desaules J-YM. Data for “Enhanced many-body quantum scars from the non-Hermitian Fock skin effect.” 2024. doi:<a href=\"https://doi.org/10.15479/AT:ISTA:17471\">10.15479/AT:ISTA:17471</a>","ista":"Desaules J-YM. 2024. Data for ‘Enhanced many-body quantum scars from the non-Hermitian Fock skin effect’, Institute of Science and Technology Austria, <a href=\"https://doi.org/10.15479/AT:ISTA:17471\">10.15479/AT:ISTA:17471</a>."},"year":"2024","publisher":"Institute of Science and Technology Austria","day":"30","file":[{"file_id":"17472","success":1,"file_size":322400,"date_created":"2024-08-30T12:55:37Z","file_name":"FiguresData.zip","relation":"main_file","access_level":"open_access","checksum":"2bd49ce5a63f1951c1ed3d89cce4fe27","creator":"jdesaule","content_type":"application/zip","date_updated":"2024-08-30T12:55:37Z"},{"relation":"main_file","access_level":"open_access","checksum":"c2ba113a241e98c394cc3ca21f3fa126","creator":"jdesaule","date_updated":"2024-08-30T13:19:57Z","content_type":"text/plain","file_id":"17473","success":1,"file_size":1368,"date_created":"2024-08-30T13:19:57Z","file_name":"readme.txt"}],"author":[{"full_name":"Desaules, Jean-Yves Marc","last_name":"Desaules","id":"6c292945-a610-11ed-9eec-c3be1ad62a80","orcid":"0000-0002-3749-6375","first_name":"Jean-Yves Marc"}],"doi":"10.15479/AT:ISTA:17471","type":"research_data","title":"Data for \"Enhanced many-body quantum scars from the non-Hermitian Fock skin effect\"","oa":1,"contributor":[{"last_name":"Shen","first_name":"Ruizhe","contributor_type":"researcher"},{"last_name":"Qin","contributor_type":"researcher","first_name":"Fang"},{"orcid":"0000-0002-3749-6375","contributor_type":"researcher","first_name":"Jean-Yves Marc","id":"6c292945-a610-11ed-9eec-c3be1ad62a80","last_name":"Desaules"},{"last_name":"Papić","first_name":"Zlatko","contributor_type":"researcher"},{"contributor_type":"researcher","first_name":"Ching Hua","last_name":"Lee"}],"department":[{"_id":"MaSe"}],"license":"https://creativecommons.org/licenses/by-nc/4.0/","month":"08","date_created":"2024-08-30T12:59:43Z","article_processing_charge":"No","related_material":{"record":[{"id":"18627","relation":"used_in_publication","status":"public"}]},"project":[{"grant_number":"101034413","call_identifier":"H2020","_id":"fc2ed2f7-9c52-11eb-aca3-c01059dda49c","name":"IST-BRIDGE: International postdoctoral program"}]},{"date_published":"2024-05-16T00:00:00Z","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"fulldoi":"https://doi.org/10.48550/arXiv.2405.10125","OA_place":"repository","date_updated":"2026-10-16T12:14:52Z","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","abstract":[{"lang":"eng","text":"The quantum approximate optimization algorithm (QAOA) uses a quantum computer\r\nto implement a variational method with $2p$ layers of alternating unitary\r\noperators, optimized by a classical computer to minimize a cost function. While\r\nrigorous performance guarantees exist for the QAOA at small depths $p$, the\r\nbehavior at large depths remains less clear, though simulations suggest\r\nexponentially fast convergence for certain problems. In this work, we gain\r\ninsights into the deep QAOA using an analytic expansion of the cost function\r\naround transition states. Transition states are constructed in a recursive\r\nmanner: from the local minima of the QAOA with $p$ layers we obtain transition\r\nstates of the QAOA with $p+1$ layers, which are stationary points characterized\r\nby a unique direction of negative curvature. We construct an analytic estimate\r\nof the negative curvature and the corresponding direction in parameter space at\r\neach transition state. The expansion of the QAOA cost function along the\r\nnegative direction to the quartic order gives a lower bound of the QAOA cost\r\nfunction improvement. We provide physical intuition behind the analytic\r\nexpressions for the local curvature and quartic expansion coefficient. Our\r\nnumerical study confirms the accuracy of our approximations and reveals that\r\nthe obtained bound and the true value of the QAOA cost function gain have a\r\ncharacteristic exponential decrease with the number of layers $p$, with the\r\nbound decreasing more rapidly. Our study establishes an analytical method for\r\nrecursively studying the QAOA that is applicable in the regime of high circuit\r\ndepth."}],"external_id":{"arxiv":["2405.10125"]},"_id":"17222","researchdata_availability":"no","status":"public","oa_version":"Preprint","das_tickbox":"0","day":"16","arxiv":1,"year":"2024","citation":{"apa":"Medina Ramos, R. A., &#38; Serbyn, M. (n.d.). A recursive lower bound on the energy improvement of the quantum approximate optimization algorithm. <i>arXiv</i>. <a href=\"https://doi.org/10.48550/arXiv.2405.10125\">https://doi.org/10.48550/arXiv.2405.10125</a>","ieee":"R. A. Medina Ramos and M. Serbyn, “A recursive lower bound on the energy improvement of the quantum approximate optimization algorithm,” <i>arXiv</i>. .","ama":"Medina Ramos RA, Serbyn M. A recursive lower bound on the energy improvement of the quantum approximate optimization algorithm. <i>arXiv</i>. doi:<a href=\"https://doi.org/10.48550/arXiv.2405.10125\">10.48550/arXiv.2405.10125</a>","ista":"Medina Ramos RA, Serbyn M. A recursive lower bound on the energy improvement of the quantum approximate optimization algorithm. arXiv, 2405.10125.","mla":"Medina Ramos, Raimel A., and Maksym Serbyn. “A Recursive Lower Bound on the Energy Improvement of the Quantum Approximate Optimization Algorithm.” <i>ArXiv</i>, 2405.10125, doi:<a href=\"https://doi.org/10.48550/arXiv.2405.10125\">10.48550/arXiv.2405.10125</a>.","short":"R.A. Medina Ramos, M. Serbyn, ArXiv (n.d.).","chicago":"Medina Ramos, Raimel A, and Maksym Serbyn. “A Recursive Lower Bound on the Energy Improvement of the Quantum Approximate Optimization Algorithm.” <i>ArXiv</i>, n.d. <a href=\"https://doi.org/10.48550/arXiv.2405.10125\">https://doi.org/10.48550/arXiv.2405.10125</a>."},"title":"A recursive lower bound on the energy improvement of the quantum approximate optimization algorithm","oa":1,"type":"preprint","doi":"10.48550/arXiv.2405.10125","main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2405.10125","open_access":"1"}],"article_number":"2405.10125","corr_author":"1","publication":"arXiv","author":[{"first_name":"Raimel A","orcid":"0000-0002-5383-2869","last_name":"Medina Ramos","id":"CE680B90-D85A-11E9-B684-C920E6697425","full_name":"Medina Ramos, Raimel A"},{"last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","orcid":"0000-0002-2399-5827","first_name":"Maksym"}],"article_processing_charge":"No","supplementarymaterial":"yes","date_created":"2024-07-10T13:12:09Z","related_material":{"record":[{"id":"17208","relation":"dissertation_contains","status":"public"}]},"publication_status":"draft","language":[{"iso":"eng"}],"department":[{"_id":"MaSe"}],"month":"05"},{"date_updated":"2026-10-16T12:14:31Z","abstract":[{"lang":"eng","text":"By patterning an ultrathin layered structure with tiny wells, physicists have created and imaged peculiar states known as quantum scars — revealing behaviour that could be used to boost the performance of electronic devices."}],"user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","article_type":"letter_note","fulldoi":"https://doi.org/10.1038/d41586-024-03649-y","date_published":"2024-11-27T00:00:00Z","OA_type":"closed access","oa_version":"None","researchdata_availability":"no","_id":"18616","status":"public","publisher":"Springer Nature","year":"2024","citation":{"ista":"Abanin D, Serbyn M. 2024. Quantum scars make their mark in graphene. Nature. 635(8040), 825–826.","ama":"Abanin D, Serbyn M. Quantum scars make their mark in graphene. <i>Nature</i>. 2024;635(8040):825-826. doi:<a href=\"https://doi.org/10.1038/d41586-024-03649-y\">10.1038/d41586-024-03649-y</a>","apa":"Abanin, D., &#38; Serbyn, M. (2024). Quantum scars make their mark in graphene. <i>Nature</i>. Springer Nature. <a href=\"https://doi.org/10.1038/d41586-024-03649-y\">https://doi.org/10.1038/d41586-024-03649-y</a>","ieee":"D. Abanin and M. Serbyn, “Quantum scars make their mark in graphene,” <i>Nature</i>, vol. 635, no. 8040. Springer Nature, pp. 825–826, 2024.","chicago":"Abanin, Dmitry, and Maksym Serbyn. “Quantum Scars Make Their Mark in Graphene.” <i>Nature</i>. Springer Nature, 2024. <a href=\"https://doi.org/10.1038/d41586-024-03649-y\">https://doi.org/10.1038/d41586-024-03649-y</a>.","mla":"Abanin, Dmitry, and Maksym Serbyn. “Quantum Scars Make Their Mark in Graphene.” <i>Nature</i>, vol. 635, no. 8040, Springer Nature, 2024, pp. 825–26, doi:<a href=\"https://doi.org/10.1038/d41586-024-03649-y\">10.1038/d41586-024-03649-y</a>.","short":"D. Abanin, M. Serbyn, Nature 635 (2024) 825–826."},"isi":1,"day":"27","das_tickbox":"0","intvolume":"       635","issue":"8040","external_id":{"isi":["001367935000029"],"pmid":["39604614"]},"scopus_import":"1","author":[{"last_name":"Abanin","full_name":"Abanin, Dmitry","first_name":"Dmitry"},{"orcid":"0000-0002-2399-5827","first_name":"Maksym","last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym"}],"publication":"Nature","type":"journal_article","doi":"10.1038/d41586-024-03649-y","title":"Quantum scars make their mark in graphene","pmid":1,"publication_identifier":{"eissn":["1476-4687"],"issn":["0028-0836"]},"publication_status":"published","department":[{"_id":"MaSe"}],"volume":635,"language":[{"iso":"eng"}],"page":"825-826","month":"11","article_processing_charge":"No","date_created":"2024-12-03T18:08:16Z","supplementarymaterial":"no","quality_controlled":"1"},{"date_updated":"2026-10-21T07:56:55Z","author":[{"full_name":"Hrast, Mateja","last_name":"Hrast","first_name":"Mateja"}],"user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","type":"research_data_reference","fulldoi":"https://doi.org/10.5281/zenodo.13833474","doi":"10.5281/zenodo.13833474","main_file_link":[{"url":"https://doi.org/10.5281/zenodo.13833475","open_access":"1"}],"oa":1,"OA_type":"green","title":"Data for: Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl","date_published":"2024-09-24T00:00:00Z","ddc":["530"],"OA_place":"repository","oa_version":"None","department":[{"_id":"MiLe"},{"_id":"MaSe"}],"_id":"22866","status":"public","publisher":"Repository","citation":{"apa":"Hrast, M. (2024). Data for: Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl. Repository. <a href=\"https://doi.org/10.5281/zenodo.13833474\">https://doi.org/10.5281/zenodo.13833474</a>","ieee":"M. Hrast, “Data for: Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl.” Repository, 2024.","ista":"Hrast M. 2024. Data for: Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl, Repository, <a href=\"https://doi.org/10.5281/zenodo.13833474\">10.5281/zenodo.13833474</a>.","ama":"Hrast M. Data for: Ab initio Auger spectrum of the ultrafast dissociating 2p3/2−1σ* resonance in HCl. 2024. doi:<a href=\"https://doi.org/10.5281/zenodo.13833474\">10.5281/zenodo.13833474</a>","mla":"Hrast, Mateja. <i>Data for: Ab Initio Auger Spectrum of the Ultrafast Dissociating 2p3/2−1σ* Resonance in HCl</i>. Repository, 2024, doi:<a href=\"https://doi.org/10.5281/zenodo.13833474\">10.5281/zenodo.13833474</a>.","short":"M. Hrast, (2024).","chicago":"Hrast, Mateja. “Data for: Ab Initio Auger Spectrum of the Ultrafast Dissociating 2p3/2−1σ* Resonance in HCl.” Repository, 2024. <a href=\"https://doi.org/10.5281/zenodo.13833474\">https://doi.org/10.5281/zenodo.13833474</a>."},"year":"2024","month":"09","day":"24","article_processing_charge":"No","date_created":"2026-09-09T09:20:36Z","related_material":{"record":[{"status":"public","id":"18710","relation":"used_in_publication"}]}},{"ddc":["530"],"date_published":"2023-03-21T00:00:00Z","has_accepted_license":"1","fulldoi":"https://doi.org/10.15479/at:ista:12732","tmp":{"name":"Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)","short":"CC BY-NC-SA (4.0)","legal_code_url":"https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode","image":"/images/cc_by_nc_sa.png"},"OA_place":"publisher","alternative_title":["ISTA Thesis"],"date_updated":"2026-04-07T13:26:32Z","user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","file_date_updated":"2023-03-23T16:43:14Z","abstract":[{"lang":"eng","text":"Nonergodic systems, whose out-of-equilibrium dynamics fail to thermalize, provide a fascinating research direction both for fundamental reasons and for application in state of the art quantum devices.\r\nGoing beyond the description of statistical mechanics, ergodicity breaking yields a new paradigm in quantum many-body physics, introducing novel phases of matter with no counterpart at equilibrium.\r\nIn this Thesis, we address different open questions in the field, focusing on disorder-induced many-body localization (MBL) and on weak ergodicity breaking in kinetically constrained models.\r\nIn particular, we contribute to the debate about transport in kinetically constrained models, studying the effect of $U(1)$ conservation and inversion-symmetry breaking in a family of quantum East models.\r\nUsing tensor network techniques, we analyze the dynamics of large MBL systems beyond the limit of exact numerical methods.\r\nIn this setting, we approach the debated topic of the coexistence of localized and thermal eigenstates separated by energy thresholds known as many-body mobility edges.\r\nInspired by recent experiments, our work further investigates the localization of a small bath induced by the coupling to a large localized chain, the so-called MBL proximity effect.\r\n\r\nIn the first Chapter, we introduce a family of particle-conserving kinetically constrained models, inspired by the quantum East model.\r\nThe system we study features strong inversion-symmetry breaking, due to the nature of the correlated hopping.\r\nWe show that these models host so-called quantum Hilbert space fragmentation, consisting of disconnected subsectors in an entangled basis, and further provide an analytical description of this phenomenon.\r\nWe further probe its effect on dynamics of simple product states, showing revivals in fidelity and local observalbes.\r\nThe study of dynamics within the largest subsector reveals an anomalous transient superdiffusive behavior crossing over to slow logarithmic dynamics at later times.\r\nThis work suggests that particle conserving constrained models with inversion-symmetry breaking realize new universality classes of dynamics and invite their further theoretical and experimental studies.\r\n\r\nNext, we use kinetic constraints and disorder to design a model with many-body mobility edges in particle density.\r\nThis feature allows to study the dynamics of localized and thermal states in large systems beyond the limitations of previous studies.\r\nThe time-evolution shows typical signatures of localization at small densities, replaced by thermal behavior at larger densities.\r\nOur results provide evidence in favor of the stability of many-body mobility edges, which was recently challenged by a theoretical argument.\r\nTo support our findings, we probe the mechanism proposed as a cause of delocalization in many-body localized systems with mobility edges suggesting its ineffectiveness in the model studied.\r\n\r\nIn the last Chapter of this Thesis, we address the topic of many-body localization proximity effect.\r\nWe study a model inspired by recent experiments, featuring Anderson localized coupled to a small bath of free hard-core bosons.\r\nThe interaction among the two particle species results in non-trivial dynamics, which we probe using tensor network techniques.\r\nOur simulations show convincing evidence of many-body localization proximity effect when the bath is composed by a single free particle and interactions are strong.\r\nWe furthter observe an anomalous entanglement dynamics, which we explain through a phenomenological theory.\r\nFinally, we extract highly excited eigenstates of large systems, providing supplementary evidence in favor of our findings."}],"ec_funded":1,"acknowledged_ssus":[{"_id":"ScienComp"}],"file":[{"content_type":"application/zip","date_updated":"2023-03-23T16:42:56Z","creator":"pbrighi","checksum":"5d2de651ef9449c1b8dc27148ca74777","access_level":"closed","relation":"source_file","file_name":"Thesis_sub_PBrighi.zip","file_size":42167561,"date_created":"2023-03-23T16:42:56Z","file_id":"12753"},{"success":1,"file_id":"12754","file_name":"Thesis_PBrighi.pdf","date_created":"2023-03-23T16:43:14Z","file_size":13977000,"access_level":"open_access","checksum":"7caa153d4a5b0873a79358787d2dfe1e","relation":"main_file","content_type":"application/pdf","date_updated":"2023-03-23T16:43:14Z","creator":"pbrighi"}],"status":"public","_id":"12732","oa_version":"Published Version","day":"21","supervisor":[{"orcid":"0000-0002-2399-5827","first_name":"Maksym","last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym"}],"citation":{"chicago":"Brighi, Pietro. “Ergodicity Breaking in Disordered and Kinetically Constrained Quantum Many-Body Systems.” Institute of Science and Technology Austria, 2023. <a href=\"https://doi.org/10.15479/at:ista:12732\">https://doi.org/10.15479/at:ista:12732</a>.","mla":"Brighi, Pietro. <i>Ergodicity Breaking in Disordered and Kinetically Constrained Quantum Many-Body Systems</i>. Institute of Science and Technology Austria, 2023, doi:<a href=\"https://doi.org/10.15479/at:ista:12732\">10.15479/at:ista:12732</a>.","short":"P. Brighi, Ergodicity Breaking in Disordered and Kinetically Constrained Quantum Many-Body Systems, Institute of Science and Technology Austria, 2023.","ama":"Brighi P. Ergodicity breaking in disordered and kinetically constrained quantum many-body systems. 2023. doi:<a href=\"https://doi.org/10.15479/at:ista:12732\">10.15479/at:ista:12732</a>","ista":"Brighi P. 2023. Ergodicity breaking in disordered and kinetically constrained quantum many-body systems. Institute of Science and Technology Austria.","ieee":"P. Brighi, “Ergodicity breaking in disordered and kinetically constrained quantum many-body systems,” Institute of Science and Technology Austria, 2023.","apa":"Brighi, P. (2023). <i>Ergodicity breaking in disordered and kinetically constrained quantum many-body systems</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:12732\">https://doi.org/10.15479/at:ista:12732</a>"},"year":"2023","publisher":"Institute of Science and Technology Austria","publication_identifier":{"issn":["2663-337X"]},"title":"Ergodicity breaking in disordered and kinetically constrained quantum many-body systems","oa":1,"doi":"10.15479/at:ista:12732","type":"dissertation","corr_author":"1","author":[{"orcid":"0000-0002-7969-2729","first_name":"Pietro","full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","last_name":"Brighi"}],"date_created":"2023-03-17T13:30:48Z","article_processing_charge":"No","project":[{"call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","grant_number":"850899"}],"degree_awarded":"PhD","related_material":{"record":[{"relation":"part_of_dissertation","id":"12750","status":"public"},{"status":"public","id":"11470","relation":"part_of_dissertation"},{"status":"public","relation":"part_of_dissertation","id":"8308"},{"status":"public","id":"11469","relation":"part_of_dissertation"}]},"page":"158","language":[{"iso":"eng"}],"department":[{"_id":"GradSch"},{"_id":"MaSe"}],"publication_status":"published","month":"03","license":"https://creativecommons.org/licenses/by-nc-sa/4.0/"},{"issue":"10","external_id":{"arxiv":["2211.02492"],"isi":["000945526400003"]},"intvolume":"       107","isi":1,"day":"01","arxiv":1,"publisher":"American Physical Society","citation":{"ama":"Ghazaryan A, Holder T, Berg E, Serbyn M. Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity. <i>Physical Review B</i>. 2023;107(10). doi:<a href=\"https://doi.org/10.1103/PhysRevB.107.104502\">10.1103/PhysRevB.107.104502</a>","ista":"Ghazaryan A, Holder T, Berg E, Serbyn M. 2023. Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity. Physical Review B. 107(10), 104502.","apa":"Ghazaryan, A., Holder, T., Berg, E., &#38; Serbyn, M. (2023). Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevB.107.104502\">https://doi.org/10.1103/PhysRevB.107.104502</a>","ieee":"A. Ghazaryan, T. Holder, E. Berg, and M. Serbyn, “Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity,” <i>Physical Review B</i>, vol. 107, no. 10. American Physical Society, 2023.","chicago":"Ghazaryan, Areg, Tobias Holder, Erez Berg, and Maksym Serbyn. “Multilayer Graphenes as a Platform for Interaction-Driven Physics and Topological Superconductivity.” <i>Physical Review B</i>. American Physical Society, 2023. <a href=\"https://doi.org/10.1103/PhysRevB.107.104502\">https://doi.org/10.1103/PhysRevB.107.104502</a>.","short":"A. Ghazaryan, T. Holder, E. Berg, M. Serbyn, Physical Review B 107 (2023).","mla":"Ghazaryan, Areg, et al. “Multilayer Graphenes as a Platform for Interaction-Driven Physics and Topological Superconductivity.” <i>Physical Review B</i>, vol. 107, no. 10, 104502, American Physical Society, 2023, doi:<a href=\"https://doi.org/10.1103/PhysRevB.107.104502\">10.1103/PhysRevB.107.104502</a>."},"acknowledgement":"E.B. and T.H. were supported by the European Research Council (ERC) under grant HQMAT (Grant Agreement No. 817799), by the Israel-USA Binational Science Foundation (BSF), and by a Research grant from Irving and Cherna Moskowitz.","year":"2023","status":"public","_id":"12790","oa_version":"Preprint","date_published":"2023-03-01T00:00:00Z","fulldoi":"https://doi.org/10.1103/PhysRevB.107.104502","article_type":"original","user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","abstract":[{"lang":"eng","text":"Motivated by the recent discoveries of superconductivity in bilayer and trilayer graphene, we theoretically investigate superconductivity and other interaction-driven phases in multilayer graphene stacks. To this end, we study the density of states of multilayer graphene with up to four layers at the single-particle band structure level in the presence of a transverse electric field. Among the considered structures, tetralayer graphene with rhombohedral (ABCA) stacking reaches the highest density of states. We study the phases that can arise in ABCA graphene by tuning the carrier density and transverse electric field. For a broad region of the tuning parameters, the presence of strong Coulomb repulsion leads to a spontaneous spin and valley symmetry breaking via Stoner transitions. Using a model that incorporates the spontaneous spin and valley polarization, we explore the Kohn-Luttinger mechanism for superconductivity driven by repulsive Coulomb interactions. We find that the strongest superconducting instability is in the p-wave channel, and occurs in proximity to the onset of Stoner transitions. Interestingly, we find a range of densities and transverse electric fields where superconductivity develops out of a strongly corrugated, singly connected Fermi surface in each valley, leading to a topologically nontrivial chiral p+ip superconducting state with an even number of copropagating chiral Majorana edge modes. Our work establishes ABCA-stacked tetralayer graphene as a promising platform for observing strongly correlated physics and topological superconductivity."}],"date_updated":"2023-08-01T13:59:29Z","quality_controlled":"1","related_material":{"link":[{"relation":"press_release","description":"News on the ISTA website","url":"https://ista.ac.at/en/news/reaching-superconductivity-layer-by-layer/"}]},"article_processing_charge":"No","date_created":"2023-04-02T22:01:10Z","month":"03","publication_status":"published","language":[{"iso":"eng"}],"volume":107,"department":[{"_id":"MaSe"},{"_id":"MiLe"}],"article_number":"104502","title":"Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity","oa":1,"publication_identifier":{"issn":["2469-9950"],"eissn":["2469-9969"]},"type":"journal_article","main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2211.02492"}],"doi":"10.1103/PhysRevB.107.104502","publication":"Physical Review B","author":[{"first_name":"Areg","orcid":"0000-0001-9666-3543","last_name":"Ghazaryan","id":"4AF46FD6-F248-11E8-B48F-1D18A9856A87","full_name":"Ghazaryan, Areg"},{"first_name":"Tobias","last_name":"Holder","full_name":"Holder, Tobias"},{"full_name":"Berg, Erez","last_name":"Berg","first_name":"Erez"},{"orcid":"0000-0002-2399-5827","first_name":"Maksym","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","last_name":"Serbyn","full_name":"Serbyn, Maksym"}],"scopus_import":"1"},{"month":"03","publication_status":"published","language":[{"iso":"eng"}],"volume":13,"department":[{"_id":"MaSe"}],"quality_controlled":"1","project":[{"_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","call_identifier":"H2020","grant_number":"850899"}],"article_processing_charge":"No","date_created":"2023-04-16T22:01:09Z","author":[{"first_name":"Marko","orcid":"0000-0003-0038-7068","last_name":"Ljubotina","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","full_name":"Ljubotina, Marko"},{"first_name":"Jean Yves","full_name":"Desaules, Jean Yves","last_name":"Desaules"},{"first_name":"Maksym","orcid":"0000-0002-2399-5827","last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym"},{"first_name":"Zlatko","full_name":"Papić, Zlatko","last_name":"Papić"}],"publication":"Physical Review X","scopus_import":"1","corr_author":"1","article_number":"011033","type":"journal_article","doi":"10.1103/PhysRevX.13.011033","oa":1,"title":"Superdiffusive energy transport in kinetically constrained models","publication_identifier":{"eissn":["2160-3308"]},"publisher":"American Physical Society","acknowledgement":"We would like to thank Alexios Michailidis, Sarang Gopalakrishnan, and Achilleas Lazarides for useful comments. M. L. and M. S. acknowledge support by the European Research Council under the European Union’s Horizon 2020 research and innovation program (Grant\r\nAgreement No. 850899). J.-Y. D. and Z. P. acknowledge support by EPSRC Grant No. EP/R513258/1 and the Leverhulme Trust Research Leadership Grant No. RL2019-015. Statement of compliance with EPSRC policy framework on research data: This publication is theoretical work that does not require supporting research data. M. S., M. L., and Z. P. acknowledge support by the Erwin Schrödinger International Institute for Mathematics and\r\nPhysics. M. L. and M. S. acknowledge PRACE for awarding us access to Joliot-Curie at GENCI@CEA, France, where the TEBD simulations were performed. The TEBD\r\nsimulations were performed using the ITENSOR library [54].","year":"2023","citation":{"chicago":"Ljubotina, Marko, Jean Yves Desaules, Maksym Serbyn, and Zlatko Papić. “Superdiffusive Energy Transport in Kinetically Constrained Models.” <i>Physical Review X</i>. American Physical Society, 2023. <a href=\"https://doi.org/10.1103/PhysRevX.13.011033\">https://doi.org/10.1103/PhysRevX.13.011033</a>.","short":"M. Ljubotina, J.Y. Desaules, M. Serbyn, Z. Papić, Physical Review X 13 (2023).","mla":"Ljubotina, Marko, et al. “Superdiffusive Energy Transport in Kinetically Constrained Models.” <i>Physical Review X</i>, vol. 13, no. 1, 011033, American Physical Society, 2023, doi:<a href=\"https://doi.org/10.1103/PhysRevX.13.011033\">10.1103/PhysRevX.13.011033</a>.","ama":"Ljubotina M, Desaules JY, Serbyn M, Papić Z. Superdiffusive energy transport in kinetically constrained models. <i>Physical Review X</i>. 2023;13(1). doi:<a href=\"https://doi.org/10.1103/PhysRevX.13.011033\">10.1103/PhysRevX.13.011033</a>","ista":"Ljubotina M, Desaules JY, Serbyn M, Papić Z. 2023. Superdiffusive energy transport in kinetically constrained models. Physical Review X. 13(1), 011033.","apa":"Ljubotina, M., Desaules, J. Y., Serbyn, M., &#38; Papić, Z. (2023). Superdiffusive energy transport in kinetically constrained models. <i>Physical Review X</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevX.13.011033\">https://doi.org/10.1103/PhysRevX.13.011033</a>","ieee":"M. Ljubotina, J. Y. Desaules, M. Serbyn, and Z. Papić, “Superdiffusive energy transport in kinetically constrained models,” <i>Physical Review X</i>, vol. 13, no. 1. American Physical Society, 2023."},"isi":1,"day":"07","oa_version":"Published Version","_id":"12839","status":"public","intvolume":"        13","file":[{"success":1,"file_id":"12845","file_name":"2023_PhysReviewX_Ljubotina.pdf","date_created":"2023-04-17T08:36:53Z","file_size":1958523,"access_level":"open_access","checksum":"ee060cea609af79bba7af74b1ce28078","relation":"main_file","content_type":"application/pdf","date_updated":"2023-04-17T08:36:53Z","creator":"dernst"}],"issue":"1","external_id":{"isi":["000957625700001"]},"ec_funded":1,"file_date_updated":"2023-04-17T08:36:53Z","abstract":[{"lang":"eng","text":"Universal nonequilibrium properties of isolated quantum systems are typically probed by studying transport of conserved quantities, such as charge or spin, while transport of energy has received considerably less attention. Here, we study infinite-temperature energy transport in the kinetically constrained PXP model describing Rydberg atom quantum simulators. Our state-of-the-art numerical simulations, including exact diagonalization and time-evolving block decimation methods, reveal the existence of two distinct transport regimes. At moderate times, the energy-energy correlation function displays periodic oscillations due to families of eigenstates forming different su(2) representations hidden within the spectrum. These families of eigenstates generalize the quantum many-body scarred states found in previous works and leave an imprint on the infinite-temperature energy transport. At later times, we observe a long-lived superdiffusive transport regime that we attribute to the proximity of a nearby integrable point. While generic strong deformations of the PXP model indeed restore diffusive transport, adding a strong chemical potential intriguingly gives rise to a well-converged superdiffusive exponent z≈3/2. Our results suggest constrained models to be potential hosts of novel transport regimes and call for developing an analytic understanding of their energy transport."}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","date_updated":"2025-04-14T07:52:07Z","tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"fulldoi":"https://doi.org/10.1103/PhysRevX.13.011033","article_type":"original","has_accepted_license":"1","date_published":"2023-03-07T00:00:00Z","ddc":["530"]},{"has_accepted_license":"1","date_published":"2023-04-14T00:00:00Z","ddc":["530"],"tmp":{"image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"keyword":["Statistical and Nonlinear Physics","Atomic and Molecular Physics","and Optics","Nuclear and High Energy Physics","Condensed Matter Physics"],"article_type":"original","fulldoi":"https://doi.org/10.21468/scipostphyscore.6.2.029","date_updated":"2025-04-14T07:43:56Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","file_date_updated":"2023-07-31T09:02:27Z","ec_funded":1,"abstract":[{"text":"Recent experimental advances have inspired the development of theoretical tools to describe the non-equilibrium dynamics of quantum systems. Among them an exact representation of quantum spin systems in terms of classical stochastic processes has been proposed. Here we provide first steps towards the extension of this stochastic approach to bosonic systems by considering the one-dimensional quantum quartic oscillator. We show how to exactly parameterize the time evolution of this prototypical model via the dynamics of a set of classical variables. We interpret these variables as stochastic processes, which allows us to propose a novel way to numerically simulate the time evolution of the system. We benchmark our findings by considering analytically solvable limits and providing alternative derivations of known results.","lang":"eng"}],"issue":"2","external_id":{"arxiv":["2211.01923"]},"intvolume":"         6","file":[{"success":1,"file_id":"13329","file_name":"2023_SciPostPhysCore_Tucci.pdf","date_created":"2023-07-31T09:02:27Z","file_size":523236,"access_level":"open_access","checksum":"b472bc82108747eda5d52adf9e2ac7f3","relation":"main_file","date_updated":"2023-07-31T09:02:27Z","content_type":"application/pdf","creator":"dernst"}],"_id":"13277","status":"public","oa_version":"Published Version","day":"14","arxiv":1,"publisher":"SciPost Foundation","citation":{"mla":"Tucci, Gennaro, et al. “Stochastic Representation of the Quantum Quartic Oscillator.” <i>SciPost Physics Core</i>, vol. 6, no. 2, 029, SciPost Foundation, 2023, doi:<a href=\"https://doi.org/10.21468/scipostphyscore.6.2.029\">10.21468/scipostphyscore.6.2.029</a>.","short":"G. Tucci, S. De Nicola, S. Wald, A. Gambassi, SciPost Physics Core 6 (2023).","chicago":"Tucci, Gennaro, Stefano De Nicola, Sascha Wald, and Andrea Gambassi. “Stochastic Representation of the Quantum Quartic Oscillator.” <i>SciPost Physics Core</i>. SciPost Foundation, 2023. <a href=\"https://doi.org/10.21468/scipostphyscore.6.2.029\">https://doi.org/10.21468/scipostphyscore.6.2.029</a>.","ieee":"G. Tucci, S. De Nicola, S. Wald, and A. Gambassi, “Stochastic representation of the quantum quartic oscillator,” <i>SciPost Physics Core</i>, vol. 6, no. 2. SciPost Foundation, 2023.","apa":"Tucci, G., De Nicola, S., Wald, S., &#38; Gambassi, A. (2023). Stochastic representation of the quantum quartic oscillator. <i>SciPost Physics Core</i>. SciPost Foundation. <a href=\"https://doi.org/10.21468/scipostphyscore.6.2.029\">https://doi.org/10.21468/scipostphyscore.6.2.029</a>","ama":"Tucci G, De Nicola S, Wald S, Gambassi A. Stochastic representation of the quantum quartic oscillator. <i>SciPost Physics Core</i>. 2023;6(2). doi:<a href=\"https://doi.org/10.21468/scipostphyscore.6.2.029\">10.21468/scipostphyscore.6.2.029</a>","ista":"Tucci G, De Nicola S, Wald S, Gambassi A. 2023. Stochastic representation of the quantum quartic oscillator. SciPost Physics Core. 6(2), 029."},"acknowledgement":"S. De Nicola acknowledges funding from the Institute of Science and Technology Austria (ISTA), and from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant Agreement No. 754411. S. De Nicola also acknowledges funding from the EPSRC Center for Doctoral Training in Cross-Disciplinary Approaches to NonEquilibrium Systems (CANES) under Grant EP/L015854/1. ","year":"2023","title":"Stochastic representation of the quantum quartic oscillator","oa":1,"publication_identifier":{"issn":["2666-9366"]},"type":"journal_article","doi":"10.21468/scipostphyscore.6.2.029","article_number":"029","corr_author":"1","scopus_import":"1","publication":"SciPost Physics Core","author":[{"first_name":"Gennaro","last_name":"Tucci","full_name":"Tucci, Gennaro"},{"full_name":"De Nicola, Stefano","id":"42832B76-F248-11E8-B48F-1D18A9856A87","last_name":"De Nicola","orcid":"0000-0002-4842-6671","first_name":"Stefano"},{"last_name":"Wald","full_name":"Wald, Sascha","first_name":"Sascha"},{"first_name":"Andrea","full_name":"Gambassi, Andrea","last_name":"Gambassi"}],"article_processing_charge":"No","date_created":"2023-07-24T10:47:46Z","project":[{"grant_number":"754411","name":"ISTplus - Postdoctoral Fellowships","_id":"260C2330-B435-11E9-9278-68D0E5697425","call_identifier":"H2020"}],"quality_controlled":"1","publication_status":"published","volume":6,"department":[{"_id":"MaSe"}],"language":[{"iso":"eng"}],"month":"04"}]