[{"month":"06","day":"12","issue":"22","oa_version":"Published Version","OA_type":"hybrid","scopus_import":"1","arxiv":1,"quality_controlled":"1","status":"public","publication_identifier":{"eissn":["2469-9969"],"issn":["2469-9950"]},"isi":1,"department":[{"_id":"MaSe"}],"date_updated":"2025-09-30T12:48:10Z","publisher":"American Physical Society","citation":{"short":"P. Brighi, M. Ljubotina, M. Serbyn, Physical Review B 111 (2025).","apa":"Brighi, P., Ljubotina, M., &#38; Serbyn, M. (2025). Probing the many-body localized spin-glass phase through quench dynamics. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/9fms-ygfz\">https://doi.org/10.1103/9fms-ygfz</a>","ista":"Brighi P, Ljubotina M, Serbyn M. 2025. Probing the many-body localized spin-glass phase through quench dynamics. Physical Review B. 111(22), L220202.","ieee":"P. Brighi, M. Ljubotina, and M. Serbyn, “Probing the many-body localized spin-glass phase through quench dynamics,” <i>Physical Review B</i>, vol. 111, no. 22. American Physical Society, 2025.","chicago":"Brighi, Pietro, Marko Ljubotina, and Maksym Serbyn. “Probing the Many-Body Localized Spin-Glass Phase through Quench Dynamics.” <i>Physical Review B</i>. American Physical Society, 2025. <a href=\"https://doi.org/10.1103/9fms-ygfz\">https://doi.org/10.1103/9fms-ygfz</a>.","mla":"Brighi, Pietro, et al. “Probing the Many-Body Localized Spin-Glass Phase through Quench Dynamics.” <i>Physical Review B</i>, vol. 111, no. 22, L220202, American Physical Society, 2025, doi:<a href=\"https://doi.org/10.1103/9fms-ygfz\">10.1103/9fms-ygfz</a>.","ama":"Brighi P, Ljubotina M, Serbyn M. Probing the many-body localized spin-glass phase through quench dynamics. <i>Physical Review B</i>. 2025;111(22). doi:<a href=\"https://doi.org/10.1103/9fms-ygfz\">10.1103/9fms-ygfz</a>"},"OA_place":"publisher","tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"volume":111,"date_published":"2025-06-12T00:00:00Z","article_processing_charge":"Yes (in subscription journal)","has_accepted_license":"1","external_id":{"isi":["001511503800006"],"arxiv":["2502.08192"]},"author":[{"first_name":"Pietro","orcid":"0000-0002-7969-2729","last_name":"Brighi","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","full_name":"Brighi, Pietro"},{"orcid":"0000-0003-0038-7068","last_name":"Ljubotina","full_name":"Ljubotina, Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","first_name":"Marko"},{"first_name":"Maksym","full_name":"Serbyn, Maksym","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","last_name":"Serbyn","orcid":"0000-0002-2399-5827"}],"title":"Probing the many-body localized spin-glass phase through quench dynamics","file":[{"file_name":"2025_PhysReviewB_Brighi.pdf","checksum":"7941f92124793a383ca132eee2c289c5","content_type":"application/pdf","date_created":"2025-06-23T06:28:17Z","date_updated":"2025-06-23T06:28:17Z","creator":"dernst","file_id":"19861","success":1,"relation":"main_file","file_size":1082749,"access_level":"open_access"}],"publication_status":"published","article_type":"letter_note","oa":1,"article_number":"L220202","project":[{"call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","grant_number":"850899","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control"}],"ec_funded":1,"abstract":[{"lang":"eng","text":"Eigenstates of quantum many-body systems are often used to define phases of matter in and out of equilibrium; however, experimentally accessing highly excited eigenstates is a challenging task, calling for alternative strategies to dynamically probe nonequilibrium phases. In this work, we characterize the dynamical properties of a disordered spin chain, focusing on the spin-glass regime. Using tensor-network simulations, we observe oscillatory behavior of local expectation values and bipartite entanglement entropy. We explain these oscillations deep in the many-body localized spin-glass regime via a simple theoretical model. From perturbation theory, we predict the timescales up to which our analytical description is valid and confirm it with numerical simulations. Finally, we study the correlation length dynamics, which, after a long-time plateau, resume growing in line with renormalization group (RG) expectations. Our work suggests that RG predictions can be quantitatively tested against numerical simulations and experiments, potentially enabling microscopic descriptions of dynamical phases in large systems."}],"publication":"Physical Review B","acknowledgement":"We thank D. A. Abanin for insightful discussions in the early stages of this work. 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 authors acknowledge support by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant Agreement No. 850899). M.L. acknowledges support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy–EXC-2111–390814868. The authors acknowledge PRACE for awarding access to Joliot-Curie at GENCI@CEA, France, where the TEBD simulations were performed. The TEBD simulations were performed using the ITensor library [52].","type":"journal_article","file_date_updated":"2025-06-23T06:28:17Z","date_created":"2025-06-13T06:09:38Z","language":[{"iso":"eng"}],"year":"2025","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","_id":"19833","intvolume":"       111","ddc":["530"],"doi":"10.1103/9fms-ygfz"},{"publication_identifier":{"eissn":["2643-1564"]},"status":"public","publisher":"American Physical Society","citation":{"short":"P. Brighi, M. Ljubotina, F. Roccati, F. Balducci, Physical Review Research 7 (2025).","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>","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.","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.","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>.","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>"},"date_updated":"2025-12-01T08:02:13Z","department":[{"_id":"MaSe"}],"date_published":"2025-10-01T00:00:00Z","volume":7,"tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"OA_place":"publisher","author":[{"full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","last_name":"Brighi","orcid":"0000-0002-7969-2729","first_name":"Pietro"},{"first_name":"Marko","last_name":"Ljubotina","orcid":"0000-0003-0038-7068","full_name":"Ljubotina, Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E"},{"last_name":"Roccati","full_name":"Roccati, Federico","first_name":"Federico"},{"last_name":"Balducci","full_name":"Balducci, Federico","first_name":"Federico"}],"article_processing_charge":"Yes (via OA deal)","has_accepted_license":"1","external_id":{"arxiv":["2504.02460"]},"month":"10","day":"01","issue":"4","quality_controlled":"1","arxiv":1,"oa_version":"Published Version","scopus_import":"1","OA_type":"gold","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.","type":"journal_article","publication":"Physical Review Research","PlanS_conform":"1","file_date_updated":"2025-12-01T08:00:19Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","year":"2025","date_created":"2025-11-30T23:02:08Z","DOAJ_listed":"1","language":[{"iso":"eng"}],"ddc":["530"],"doi":"10.1103/crwj-x7j8","intvolume":"         7","_id":"20709","file":[{"date_created":"2025-12-01T08:00:19Z","checksum":"c4e582ab64ab9f8fface70bf2fd31882","content_type":"application/pdf","file_name":"2025_PhysReviewResearch_Brighi.pdf","file_size":483879,"access_level":"open_access","success":1,"relation":"main_file","file_id":"20715","date_updated":"2025-12-01T08:00:19Z","creator":"dernst"}],"title":"Finite steady-state current defies non-Hermitian many-body localization","article_number":"L042014","oa":1,"publication_status":"published","article_type":"original","abstract":[{"lang":"eng","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."}]},{"author":[{"id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","full_name":"Brighi, Pietro","orcid":"0000-0002-7969-2729","last_name":"Brighi","first_name":"Pietro"},{"first_name":"Marko","last_name":"Ljubotina","orcid":"0000-0003-0038-7068","full_name":"Ljubotina, Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E"}],"article_processing_charge":"No","external_id":{"isi":["001361617100003"],"arxiv":["2405.02102"]},"date_published":"2024-09-11T00:00:00Z","volume":110,"citation":{"ista":"Brighi P, Ljubotina M. 2024. Anomalous transport in the kinetically constrained quantum East-West model. Physical Review B. 110(10), L100304.","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>","short":"P. Brighi, M. Ljubotina, Physical Review B 110 (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>","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>.","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>.","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."},"publisher":"American Physical Society","date_updated":"2025-09-08T09:49:29Z","corr_author":"1","department":[{"_id":"MaSe"}],"isi":1,"publication_identifier":{"eissn":["2469-9969"],"issn":["2469-9950"]},"status":"public","quality_controlled":"1","arxiv":1,"scopus_import":"1","oa_version":"Preprint","issue":"10","day":"11","month":"09","doi":"10.1103/PhysRevB.110.L100304","intvolume":"       110","_id":"18110","year":"2024","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","date_created":"2024-09-22T22:01:42Z","language":[{"iso":"eng"}],"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).","type":"journal_article","publication":"Physical Review B","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."}],"ec_funded":1,"project":[{"name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","grant_number":"850899","call_identifier":"H2020"}],"article_number":"L100304","main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2405.02102"}],"oa":1,"publication_status":"published","article_type":"letter_note","title":"Anomalous transport in the kinetically constrained quantum East-West model"},{"article_processing_charge":"Yes (in subscription journal)","external_id":{"arxiv":["2303.16876"]},"has_accepted_license":"1","author":[{"full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","orcid":"0000-0002-7969-2729","last_name":"Brighi","first_name":"Pietro"},{"first_name":"Marko","full_name":"Ljubotina, Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","last_name":"Ljubotina","orcid":"0000-0003-0038-7068"},{"full_name":"Abanin, Dmitry A.","last_name":"Abanin","first_name":"Dmitry A."},{"id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","orcid":"0000-0002-2399-5827","last_name":"Serbyn","first_name":"Maksym"}],"volume":108,"date_published":"2023-08-01T00:00:00Z","tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"corr_author":"1","department":[{"_id":"MaSe"}],"publisher":"American Physical Society","citation":{"apa":"Brighi, P., Ljubotina, M., Abanin, D. A., &#38; Serbyn, M. (2023). Many-body localization proximity effect in a two-species bosonic Hubbard model. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevb.108.054201\">https://doi.org/10.1103/physrevb.108.054201</a>","ista":"Brighi P, Ljubotina M, Abanin DA, Serbyn M. 2023. Many-body localization proximity effect in a two-species bosonic Hubbard model. Physical Review B. 108(5), 054201.","short":"P. Brighi, M. Ljubotina, D.A. Abanin, M. Serbyn, Physical Review B 108 (2023).","ama":"Brighi P, Ljubotina M, Abanin DA, Serbyn M. Many-body localization proximity effect in a two-species bosonic Hubbard model. <i>Physical Review B</i>. 2023;108(5). doi:<a href=\"https://doi.org/10.1103/physrevb.108.054201\">10.1103/physrevb.108.054201</a>","ieee":"P. Brighi, M. Ljubotina, D. A. Abanin, and M. Serbyn, “Many-body localization proximity effect in a two-species bosonic Hubbard model,” <i>Physical Review B</i>, vol. 108, no. 5. American Physical Society, 2023.","mla":"Brighi, Pietro, et al. “Many-Body Localization Proximity Effect in a Two-Species Bosonic Hubbard Model.” <i>Physical Review B</i>, vol. 108, no. 5, 054201, American Physical Society, 2023, doi:<a href=\"https://doi.org/10.1103/physrevb.108.054201\">10.1103/physrevb.108.054201</a>.","chicago":"Brighi, Pietro, Marko Ljubotina, Dmitry A. Abanin, and Maksym Serbyn. “Many-Body Localization Proximity Effect in a Two-Species Bosonic Hubbard Model.” <i>Physical Review B</i>. American Physical Society, 2023. <a href=\"https://doi.org/10.1103/physrevb.108.054201\">https://doi.org/10.1103/physrevb.108.054201</a>."},"date_updated":"2025-04-14T07:52:06Z","status":"public","publication_identifier":{"issn":["2469-9950"],"eissn":["2469-9969"]},"arxiv":1,"oa_version":"Published Version","scopus_import":"1","quality_controlled":"1","issue":"5","day":"01","month":"08","_id":"13963","doi":"10.1103/physrevb.108.054201","ddc":["530"],"intvolume":"       108","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","year":"2023","date_created":"2023-08-05T18:25:22Z","language":[{"iso":"eng"}],"file_date_updated":"2023-08-07T09:48:08Z","publication":"Physical Review B","type":"journal_article","acknowledgement":"We thank A. A. Michailidis and A. Mirlin for insightful discussions. P.B., M.L., and M.S. acknowledge support by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899). D.A. was\r\nsupported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 864597) and by the Swiss National Science Foundation. P.B., 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 simulations were performed using the ITensor library [60].","abstract":[{"text":"The many-body localization (MBL) proximity effect is an intriguing phenomenon where a thermal bath localizes due to the interaction with a disordered system. The interplay of thermal and nonergodic behavior in these systems gives rise to a rich phase diagram, whose exploration is an active field of research. In this paper, we study a bosonic Hubbard model featuring two particle species representing the bath and the disordered system. Using state-of-the-art numerical techniques, we investigate the dynamics of the model in different regimes, based on which we obtain a tentative phase diagram as a function of coupling strength and bath size. When the bath is composed of a single particle, we observe clear signatures of a transition from an MBL proximity effect to a delocalized phase. Increasing the bath size, however, its thermalizing effect becomes stronger and eventually the whole system delocalizes in the range of moderate interaction strengths studied. In this regime, we characterize particle transport, revealing diffusive behavior of the originally localized bosons.","lang":"eng"}],"project":[{"name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","grant_number":"850899","call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E"}],"ec_funded":1,"oa":1,"article_type":"original","publication_status":"published","article_number":"054201","file":[{"relation":"main_file","success":1,"access_level":"open_access","file_size":3051398,"creator":"dernst","date_updated":"2023-08-07T09:48:08Z","file_id":"13981","date_created":"2023-08-07T09:48:08Z","file_name":"2023_PhysRevB_Brighi.pdf","checksum":"f763000339b5fd543c14377109920690","content_type":"application/pdf"}],"title":"Many-body localization proximity effect in a two-species bosonic Hubbard model"},{"issue":"3","quality_controlled":"1","arxiv":1,"oa_version":"Published Version","scopus_import":"1","month":"09","keyword":["General Physics and Astronomy"],"day":"13","volume":15,"date_published":"2023-09-13T00:00:00Z","tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"related_material":{"record":[{"status":"public","id":"12750","relation":"earlier_version"}]},"author":[{"first_name":"Pietro","last_name":"Brighi","orcid":"0000-0002-7969-2729","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","full_name":"Brighi, Pietro"},{"id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","full_name":"Ljubotina, Marko","last_name":"Ljubotina","orcid":"0000-0003-0038-7068","first_name":"Marko"},{"first_name":"Maksym","last_name":"Serbyn","orcid":"0000-0002-2399-5827","full_name":"Serbyn, Maksym","id":"47809E7E-F248-11E8-B48F-1D18A9856A87"}],"article_processing_charge":"No","external_id":{"arxiv":["2210.15607"]},"has_accepted_license":"1","publication_identifier":{"issn":["2542-4653"]},"status":"public","citation":{"short":"P. Brighi, M. Ljubotina, M. Serbyn, SciPost Physics 15 (2023).","ista":"Brighi P, Ljubotina M, Serbyn M. 2023. Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. SciPost Physics. 15(3), 093.","apa":"Brighi, P., Ljubotina, M., &#38; Serbyn, M. (2023). Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. <i>SciPost Physics</i>. SciPost Foundation. <a href=\"https://doi.org/10.21468/scipostphys.15.3.093\">https://doi.org/10.21468/scipostphys.15.3.093</a>","mla":"Brighi, Pietro, et al. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving Quantum East Models.” <i>SciPost Physics</i>, vol. 15, no. 3, 093, SciPost Foundation, 2023, doi:<a href=\"https://doi.org/10.21468/scipostphys.15.3.093\">10.21468/scipostphys.15.3.093</a>.","chicago":"Brighi, Pietro, Marko Ljubotina, and Maksym Serbyn. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving Quantum East Models.” <i>SciPost Physics</i>. SciPost Foundation, 2023. <a href=\"https://doi.org/10.21468/scipostphys.15.3.093\">https://doi.org/10.21468/scipostphys.15.3.093</a>.","ieee":"P. Brighi, M. Ljubotina, and M. Serbyn, “Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models,” <i>SciPost Physics</i>, vol. 15, no. 3. SciPost Foundation, 2023.","ama":"Brighi P, Ljubotina M, Serbyn M. Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. <i>SciPost Physics</i>. 2023;15(3). doi:<a href=\"https://doi.org/10.21468/scipostphys.15.3.093\">10.21468/scipostphys.15.3.093</a>"},"publisher":"SciPost Foundation","date_updated":"2025-04-14T07:52:05Z","corr_author":"1","department":[{"_id":"MaSe"}],"ec_funded":1,"project":[{"name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","grant_number":"850899","call_identifier":"H2020"}],"abstract":[{"text":"Quantum kinetically constrained models have recently attracted significant attention due to their anomalous dynamics and thermalization. In this work, we introduce a hitherto unexplored family of kinetically constrained models featuring conserved particle number and strong inversion-symmetry breaking due to facilitated hopping. We demonstrate that these models provide a generic example of so-called quantum Hilbert space fragmentation, that is manifested in disconnected sectors in the Hilbert space that are not apparent in the computational basis. Quantum Hilbert space fragmentation leads to an exponential in system size number of eigenstates with exactly zero entanglement entropy across several bipartite cuts. These eigenstates can be probed dynamically using quenches from simple initial product states. In addition, we study the particle spreading under unitary dynamics launched from the domain wall state, and find faster than diffusive dynamics at high particle densities, that crosses over into logarithmically slow relaxation at smaller densities. Using a classically simulable cellular automaton, we reproduce the logarithmic dynamics observed in the quantum case. Our work suggests that particle conserving constrained models with inversion symmetry breaking realize so far unexplored dynamical behavior and invite their further theoretical and experimental studies.","lang":"eng"}],"file":[{"success":1,"relation":"main_file","file_size":4866506,"access_level":"open_access","date_updated":"2023-09-20T10:46:10Z","creator":"dernst","file_id":"14350","date_created":"2023-09-20T10:46:10Z","file_name":"2023_SciPostPhysics_Brighi.pdf","checksum":"4cef6a8021f6b6c47ab2f2f2b1387ac2","content_type":"application/pdf"}],"title":"Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models","article_number":"093","oa":1,"publication_status":"published","article_type":"original","year":"2023","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_created":"2023-09-14T13:08:23Z","language":[{"iso":"eng"}],"doi":"10.21468/scipostphys.15.3.093","ddc":["530"],"intvolume":"        15","_id":"14334","acknowledgement":"We would like to thank Raimel A. Medina, Hansveer Singh, and Dmitry Abanin for useful\r\ndiscussions.The authors acknowledge support by the European Research Council\r\n(ERC) under the European Union’s Horizon 2020 research and innovation program (Grant\r\nAgreement No. 850899). We acknowledge support by the Erwin Schrödinger International\r\nInstitute for Mathematics and Physics (ESI).","type":"journal_article","publication":"SciPost Physics","file_date_updated":"2023-09-20T10:46:10Z"},{"oa":1,"publication_status":"published","alternative_title":["ISTA Thesis"],"page":"158","degree_awarded":"PhD","title":"Ergodicity breaking in disordered and kinetically constrained quantum many-body systems","file":[{"file_name":"Thesis_sub_PBrighi.zip","checksum":"5d2de651ef9449c1b8dc27148ca74777","content_type":"application/zip","date_created":"2023-03-23T16:42:56Z","creator":"pbrighi","date_updated":"2023-03-23T16:42:56Z","file_id":"12753","relation":"source_file","access_level":"closed","file_size":42167561},{"access_level":"open_access","file_size":13977000,"success":1,"relation":"main_file","file_id":"12754","creator":"pbrighi","date_updated":"2023-03-23T16:43:14Z","date_created":"2023-03-23T16:43:14Z","checksum":"7caa153d4a5b0873a79358787d2dfe1e","content_type":"application/pdf","file_name":"Thesis_PBrighi.pdf"}],"supervisor":[{"id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","orcid":"0000-0002-2399-5827","last_name":"Serbyn","first_name":"Maksym"}],"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,"project":[{"call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","grant_number":"850899","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control"}],"file_date_updated":"2023-03-23T16:43:14Z","type":"dissertation","doi":"10.15479/at:ista:12732","ddc":["530"],"_id":"12732","year":"2023","user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","acknowledged_ssus":[{"_id":"ScienComp"}],"date_created":"2023-03-17T13:30:48Z","language":[{"iso":"eng"}],"day":"21","month":"03","oa_version":"Published Version","publisher":"Institute of Science and Technology Austria","citation":{"ieee":"P. Brighi, “Ergodicity breaking in disordered and kinetically constrained quantum many-body systems,” Institute of Science and Technology Austria, 2023.","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>.","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>.","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>","short":"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>","ista":"Brighi P. 2023. Ergodicity breaking in disordered and kinetically constrained quantum many-body systems. Institute of Science and Technology Austria."},"date_updated":"2026-04-07T13:26:32Z","corr_author":"1","department":[{"_id":"GradSch"},{"_id":"MaSe"}],"publication_identifier":{"issn":["2663-337X"]},"status":"public","author":[{"first_name":"Pietro","full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","orcid":"0000-0002-7969-2729","last_name":"Brighi"}],"article_processing_charge":"No","has_accepted_license":"1","date_published":"2023-03-21T00:00:00Z","tmp":{"short":"CC BY-NC-SA (4.0)","name":"Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (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","related_material":{"record":[{"status":"public","id":"12750","relation":"part_of_dissertation"},{"status":"public","id":"11470","relation":"part_of_dissertation"},{"relation":"part_of_dissertation","id":"8308","status":"public"},{"id":"11469","relation":"part_of_dissertation","status":"public"}]}},{"publication":"Physical Review B","acknowledgement":"We thank M. Ljubotina for insightful discussions. P. B., A. M. and M. S. acknowledge support by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899). D. A. was supported by the Swiss National Science Foundation and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 864597). The development of parallel TEBD code was supported by S. Elefante from the Scientific Computing (SciComp) that is part of Scientific Service Units (SSU) of IST Austria. Some of the computations were performed on the Baobab cluster of the University of Geneva.","type":"journal_article","year":"2022","acknowledged_ssus":[{"_id":"ScienComp"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_created":"2022-06-29T20:19:51Z","language":[{"iso":"eng"}],"_id":"11469","intvolume":"       105","doi":"10.1103/physrevb.105.224208","title":"Localization of a mobile impurity interacting with an Anderson insulator","oa":1,"main_file_link":[{"url":" https://doi.org/10.48550/arXiv.2111.08603","open_access":"1"}],"publication_status":"published","article_type":"original","article_number":"224208","project":[{"name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","call_identifier":"H2020","grant_number":"850899","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E"}],"ec_funded":1,"abstract":[{"text":"Thermalizing and localized many-body quantum systems present two distinct dynamical phases of matter. Recently the fate of a localized system coupled to a thermalizing system viewed as a quantum bath received significant theoretical and experimental attention. In this work, we study a mobile impurity, representing a small quantum bath, that interacts locally with an Anderson insulator with a finite density of localized particles. Using static Hartree approximation to obtain an effective disorder strength, we formulate an analytic criterion for the perturbative stability of the localization. Next, we use an approximate dynamical Hartree method and the quasi-exact time-evolved block decimation (TEBD) algorithm to study the dynamics of the system. We find that the dynamical Hartree approach which completely ignores entanglement between the impurity and localized particles predicts the delocalization of the system. In contrast, the full numerical simulation of the unitary dynamics with TEBD suggests the stability of localization on numerically accessible timescales. Finally, using an extension of the density matrix renormalization group algorithm to excited states (DMRG-X), we approximate the highly excited eigenstates of the system. We find that the impurity remains localized in the eigenstates and entanglement is enhanced in a finite region around the position of the impurity, confirming the dynamical predictions. Dynamics and the DMRG-X results provide compelling evidence for the stability of localization.","lang":"eng"}],"status":"public","isi":1,"publication_identifier":{"issn":["2469-9950"],"eissn":["2469-9969"]},"corr_author":"1","department":[{"_id":"MaSe"}],"publisher":"American Physical Society","citation":{"ama":"Brighi P, Michailidis A, Kirova K, Abanin DA, Serbyn M. Localization of a mobile impurity interacting with an Anderson insulator. <i>Physical Review B</i>. 2022;105(22). doi:<a href=\"https://doi.org/10.1103/physrevb.105.224208\">10.1103/physrevb.105.224208</a>","chicago":"Brighi, Pietro, Alexios Michailidis, Kristina Kirova, Dmitry A. Abanin, and Maksym Serbyn. “Localization of a Mobile Impurity Interacting with an Anderson Insulator.” <i>Physical Review B</i>. American Physical Society, 2022. <a href=\"https://doi.org/10.1103/physrevb.105.224208\">https://doi.org/10.1103/physrevb.105.224208</a>.","mla":"Brighi, Pietro, et al. “Localization of a Mobile Impurity Interacting with an Anderson Insulator.” <i>Physical Review B</i>, vol. 105, no. 22, 224208, American Physical Society, 2022, doi:<a href=\"https://doi.org/10.1103/physrevb.105.224208\">10.1103/physrevb.105.224208</a>.","ieee":"P. Brighi, A. Michailidis, K. Kirova, D. A. Abanin, and M. Serbyn, “Localization of a mobile impurity interacting with an Anderson insulator,” <i>Physical Review B</i>, vol. 105, no. 22. American Physical Society, 2022.","ista":"Brighi P, Michailidis A, Kirova K, Abanin DA, Serbyn M. 2022. Localization of a mobile impurity interacting with an Anderson insulator. Physical Review B. 105(22), 224208.","apa":"Brighi, P., Michailidis, A., Kirova, K., Abanin, D. A., &#38; Serbyn, M. (2022). Localization of a mobile impurity interacting with an Anderson insulator. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevb.105.224208\">https://doi.org/10.1103/physrevb.105.224208</a>","short":"P. Brighi, A. Michailidis, K. Kirova, D.A. Abanin, M. Serbyn, Physical Review B 105 (2022)."},"date_updated":"2026-04-07T13:26:31Z","related_material":{"record":[{"id":"12732","relation":"dissertation_contains","status":"public"}]},"volume":105,"date_published":"2022-06-27T00:00:00Z","article_processing_charge":"No","external_id":{"isi":["000823050000001"],"arxiv":["2111.08603"]},"author":[{"first_name":"Pietro","full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","orcid":"0000-0002-7969-2729","last_name":"Brighi"},{"id":"36EBAD38-F248-11E8-B48F-1D18A9856A87","full_name":"Michailidis, Alexios","orcid":"0000-0002-8443-1064","last_name":"Michailidis","first_name":"Alexios"},{"first_name":"Kristina","id":"4aeda2ae-f847-11ec-98e0-c4a66fe174d4","full_name":"Kirova, Kristina","last_name":"Kirova"},{"first_name":"Dmitry A.","last_name":"Abanin","full_name":"Abanin, Dmitry A."},{"last_name":"Serbyn","orcid":"0000-0002-2399-5827","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","first_name":"Maksym"}],"month":"06","day":"27","issue":"22","arxiv":1,"oa_version":"Preprint","scopus_import":"1","quality_controlled":"1"},{"isi":1,"publication_identifier":{"issn":["2469-9950"],"eissn":["2469-9969"]},"status":"public","publisher":"American Physical Society","citation":{"chicago":"Brighi, Pietro, Alexios A. Michailidis, Dmitry A. Abanin, and Maksym Serbyn. “Propagation of Many-Body Localization in an Anderson Insulator.” <i>Physical Review B</i>. American Physical Society, 2022. <a href=\"https://doi.org/10.1103/physrevb.105.l220203\">https://doi.org/10.1103/physrevb.105.l220203</a>.","mla":"Brighi, Pietro, et al. “Propagation of Many-Body Localization in an Anderson Insulator.” <i>Physical Review B</i>, vol. 105, no. 22, L220203, American Physical Society, 2022, doi:<a href=\"https://doi.org/10.1103/physrevb.105.l220203\">10.1103/physrevb.105.l220203</a>.","ieee":"P. Brighi, A. A. Michailidis, D. A. Abanin, and M. Serbyn, “Propagation of many-body localization in an Anderson insulator,” <i>Physical Review B</i>, vol. 105, no. 22. American Physical Society, 2022.","ama":"Brighi P, Michailidis AA, Abanin DA, Serbyn M. Propagation of many-body localization in an Anderson insulator. <i>Physical Review B</i>. 2022;105(22). doi:<a href=\"https://doi.org/10.1103/physrevb.105.l220203\">10.1103/physrevb.105.l220203</a>","short":"P. Brighi, A.A. Michailidis, D.A. Abanin, M. Serbyn, Physical Review B 105 (2022).","ista":"Brighi P, Michailidis AA, Abanin DA, Serbyn M. 2022. Propagation of many-body localization in an Anderson insulator. Physical Review B. 105(22), L220203.","apa":"Brighi, P., Michailidis, A. A., Abanin, D. A., &#38; Serbyn, M. (2022). Propagation of many-body localization in an Anderson insulator. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevb.105.l220203\">https://doi.org/10.1103/physrevb.105.l220203</a>"},"date_updated":"2026-04-07T13:26:31Z","corr_author":"1","department":[{"_id":"MaSe"}],"volume":105,"date_published":"2022-06-27T00:00:00Z","related_material":{"record":[{"status":"public","id":"12732","relation":"dissertation_contains"}]},"author":[{"orcid":"0000-0002-7969-2729","last_name":"Brighi","full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","first_name":"Pietro"},{"first_name":"Alexios A.","last_name":"Michailidis","full_name":"Michailidis, Alexios A."},{"full_name":"Abanin, Dmitry A.","last_name":"Abanin","first_name":"Dmitry A."},{"id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","orcid":"0000-0002-2399-5827","last_name":"Serbyn","first_name":"Maksym"}],"external_id":{"arxiv":["2109.07332"],"isi":["000823050000012"]},"article_processing_charge":"No","month":"06","day":"27","issue":"22","quality_controlled":"1","arxiv":1,"scopus_import":"1","oa_version":"Preprint","acknowledgement":"We acknowledge useful discussions with M. Ljubotina. P. B., A. M., and M. S. were supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899). D.A. was supported by the Swiss National Science Foundation and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 864597). The development of parallel TEBD code was was supported by S. Elefante from the Scientific Computing (SciComp) that is part of Scientific Service Units (SSU) of IST Austria. Some of the computations were performed on the Baobab cluster of the University of Geneva.","type":"journal_article","publication":"Physical Review B","year":"2022","acknowledged_ssus":[{"_id":"ScienComp"}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","language":[{"iso":"eng"}],"date_created":"2022-06-29T20:20:47Z","intvolume":"       105","doi":"10.1103/physrevb.105.l220203","_id":"11470","title":"Propagation of many-body localization in an Anderson insulator","article_number":"L220203","oa":1,"main_file_link":[{"open_access":"1","url":" https://doi.org/10.48550/arXiv.2109.07332"}],"publication_status":"published","article_type":"original","ec_funded":1,"project":[{"_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","call_identifier":"H2020","grant_number":"850899","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control"}],"abstract":[{"text":"Many-body localization (MBL) is an example of a dynamical phase of matter that avoids thermalization. While the MBL phase is robust to weak local perturbations, the fate of an MBL system coupled to a thermalizing quantum system that represents a “heat bath” is an open question that is actively investigated theoretically and experimentally. In this work, we consider the stability of an Anderson insulator with a finite density of particles interacting with a single mobile impurity—a small quantum bath. We give perturbative arguments that support the stability of localization in the strong interaction regime. Large-scale tensor network simulations of dynamics are employed to corroborate the presence of the localized phase and give quantitative predictions in the thermodynamic limit. We develop a phenomenological description of the dynamics in the strong interaction regime, and we demonstrate that the impurity effectively turns the Anderson insulator into an MBL phase, giving rise to nontrivial entanglement dynamics well captured by our phenomenology.","lang":"eng"}]},{"tmp":{"short":"CC BY-NC-SA (4.0)","name":"Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (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"},"date_created":"2023-03-23T14:33:13Z","language":[{"iso":"eng"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_published":"2022-11-07T00:00:00Z","year":"2022","related_material":{"record":[{"id":"14334","relation":"later_version","status":"public"},{"status":"public","id":"12732","relation":"dissertation_contains"}]},"OA_place":"repository","doi":"10.48550/arXiv.2210.15607","author":[{"first_name":"Pietro","orcid":"0000-0002-7969-2729","last_name":"Brighi","full_name":"Brighi, Pietro","id":"4115AF5C-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0003-0038-7068","last_name":"Ljubotina","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E","full_name":"Ljubotina, Marko","first_name":"Marko"},{"last_name":"Serbyn","orcid":"0000-0002-2399-5827","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym","first_name":"Maksym"}],"external_id":{"arxiv":["2210.15607"]},"article_processing_charge":"No","_id":"12750","type":"preprint","status":"public","publication":"arXiv","date_updated":"2026-04-07T13:26:31Z","citation":{"apa":"Brighi, P., Ljubotina, M., &#38; Serbyn, M. (n.d.). Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. <i>arXiv</i>. <a href=\"https://doi.org/10.48550/arXiv.2210.15607\">https://doi.org/10.48550/arXiv.2210.15607</a>","ista":"Brighi P, Ljubotina M, Serbyn M. Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. arXiv, 2210.15607.","short":"P. Brighi, M. Ljubotina, M. Serbyn, ArXiv (n.d.).","ama":"Brighi P, Ljubotina M, Serbyn M. Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. <i>arXiv</i>. doi:<a href=\"https://doi.org/10.48550/arXiv.2210.15607\">10.48550/arXiv.2210.15607</a>","ieee":"P. Brighi, M. Ljubotina, and M. Serbyn, “Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models,” <i>arXiv</i>. .","chicago":"Brighi, Pietro, Marko Ljubotina, and Maksym Serbyn. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving Quantum East Models.” <i>ArXiv</i>, n.d. <a href=\"https://doi.org/10.48550/arXiv.2210.15607\">https://doi.org/10.48550/arXiv.2210.15607</a>.","mla":"Brighi, Pietro, et al. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving Quantum East Models.” <i>ArXiv</i>, 2210.15607, doi:<a href=\"https://doi.org/10.48550/arXiv.2210.15607\">10.48550/arXiv.2210.15607</a>."},"department":[{"_id":"GradSch"},{"_id":"MaSe"}],"corr_author":"1","abstract":[{"lang":"eng","text":"Quantum kinetically constrained models have recently attracted significant attention due to their anomalous dynamics and thermalization. In this work, we introduce a hitherto unexplored family of kinetically constrained models featuring a conserved particle number and strong inversion-symmetry breaking due to facilitated hopping. We demonstrate that these models provide a generic example of so-called quantum Hilbert space fragmentation, that is manifested in disconnected sectors in the Hilbert space that are not apparent in the computational basis. Quantum Hilbert space fragmentation leads to an exponential in system size number of eigenstates with exactly zero entanglement entropy across several bipartite cuts. These eigenstates can be probed dynamically using quenches from simple initial product states. In addition, we study the particle spreading under unitary dynamics launched from the domain wall state, and find faster than diffusive dynamics at high particle densities, that crosses over into logarithmically slow relaxation at smaller densities. Using a classically simulable cellular automaton, we reproduce the logarithmic dynamics observed in the quantum case. Our work suggests that particle conserving constrained models with inversion symmetry breaking realize so far unexplored universality classes of dynamics and invite their further theoretical and experimental studies."}],"oa_version":"Preprint","arxiv":1,"title":"Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models","month":"11","article_number":"2210.15607","day":"07","publication_status":"draft","oa":1,"main_file_link":[{"url":"https://doi.org/10.48550/arXiv.2210.15607","open_access":"1"}]},{"ddc":["530"],"doi":"10.1103/physrevb.102.060202","intvolume":"       102","_id":"8308","language":[{"iso":"eng"}],"date_created":"2020-08-26T19:27:42Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","year":"2020","file_date_updated":"2020-08-26T19:29:00Z","type":"journal_article","acknowledgement":"Acknowledgments. We acknowledge useful discussions with W. De Roeck and A. Michailidis. P.B. was supported by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 665385. D.A. was supported by the Swiss National Science Foundation. M.S. was supported by European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant Agreement No. 850899). This work benefited from visits to KITP, supported by the National Science Foundation under Grant No. NSF PHY-1748958 and from the program “Thermalization, Many Body Localization and Hydrodynamics” at International Centre for Theoretical Sciences (Code: ICTS/hydrodynamics2019/11).","publication":"Physical Review B","abstract":[{"text":"Many-body localization provides a mechanism to avoid thermalization in isolated interacting quantum systems. The breakdown of thermalization may be complete, when all eigenstates in the many-body spectrum become localized, or partial, when the so-called many-body mobility edge separates localized and delocalized parts of the spectrum. Previously, De Roeck et al. [Phys. Rev. B 93, 014203 (2016)] suggested a possible instability of the many-body mobility edge in energy density. The local ergodic regions—so-called “bubbles”—resonantly spread throughout the system, leading to delocalization. In order to study such instability mechanism, in this work we design a model featuring many-body mobility edge in particle density: the states at small particle density are localized, while increasing the density of particles leads to delocalization. Using numerical simulations with matrix product states, we demonstrate the stability of many-body localization with respect to small bubbles in large dilute systems for experimentally relevant timescales. In addition, we demonstrate that processes where the bubble spreads are favored over processes that lead to resonant tunneling, suggesting a possible mechanism behind the observed stability of many-body mobility edge. We conclude by proposing experiments to probe particle density mobility edge in the Bose-Hubbard model.","lang":"eng"}],"ec_funded":1,"project":[{"name":"International IST Doctoral Program","grant_number":"665385","call_identifier":"H2020","_id":"2564DBCA-B435-11E9-9278-68D0E5697425"},{"name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control","call_identifier":"H2020","grant_number":"850899","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E"}],"article_number":"060202(R)","publication_status":"published","article_type":"original","oa":1,"title":"Stability of mobility edges in disordered interacting systems","file":[{"file_id":"8309","date_updated":"2020-08-26T19:28:55Z","creator":"mserbyn","file_size":488825,"access_level":"open_access","success":1,"relation":"main_file","checksum":"716442fa7861323fcc80b93718ca009c","content_type":"application/pdf","file_name":"PhysRevB.102.060202.pdf","date_created":"2020-08-26T19:28:55Z"},{"file_id":"8310","date_updated":"2020-08-26T19:29:00Z","creator":"mserbyn","file_size":711405,"access_level":"open_access","success":1,"relation":"main_file","content_type":"application/pdf","checksum":"be0abdc8f60fe065ea6dc92e08487122","file_name":"Supplementary-mbme.pdf","date_created":"2020-08-26T19:29:00Z"}],"author":[{"id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","full_name":"Brighi, Pietro","orcid":"0000-0002-7969-2729","last_name":"Brighi","first_name":"Pietro"},{"last_name":"Abanin","full_name":"Abanin, Dmitry A.","first_name":"Dmitry A."},{"first_name":"Maksym","orcid":"0000-0002-2399-5827","last_name":"Serbyn","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","full_name":"Serbyn, Maksym"}],"article_processing_charge":"No","has_accepted_license":"1","external_id":{"arxiv":["2005.02999"],"isi":["000562628300001"]},"date_published":"2020-08-26T00:00:00Z","volume":102,"OA_place":"repository","related_material":{"record":[{"status":"public","id":"12732","relation":"dissertation_contains"}]},"date_updated":"2026-04-07T13:26:31Z","citation":{"ama":"Brighi P, Abanin DA, Serbyn M. Stability of mobility edges in disordered interacting systems. <i>Physical Review B</i>. 2020;102(6). doi:<a href=\"https://doi.org/10.1103/physrevb.102.060202\">10.1103/physrevb.102.060202</a>","mla":"Brighi, Pietro, et al. “Stability of Mobility Edges in Disordered Interacting Systems.” <i>Physical Review B</i>, vol. 102, no. 6, 060202(R), American Physical Society, 2020, doi:<a href=\"https://doi.org/10.1103/physrevb.102.060202\">10.1103/physrevb.102.060202</a>.","chicago":"Brighi, Pietro, Dmitry A. Abanin, and Maksym Serbyn. “Stability of Mobility Edges in Disordered Interacting Systems.” <i>Physical Review B</i>. American Physical Society, 2020. <a href=\"https://doi.org/10.1103/physrevb.102.060202\">https://doi.org/10.1103/physrevb.102.060202</a>.","ieee":"P. Brighi, D. A. Abanin, and M. Serbyn, “Stability of mobility edges in disordered interacting systems,” <i>Physical Review B</i>, vol. 102, no. 6. American Physical Society, 2020.","ista":"Brighi P, Abanin DA, Serbyn M. 2020. Stability of mobility edges in disordered interacting systems. Physical Review B. 102(6), 060202(R).","apa":"Brighi, P., Abanin, D. A., &#38; Serbyn, M. (2020). Stability of mobility edges in disordered interacting systems. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevb.102.060202\">https://doi.org/10.1103/physrevb.102.060202</a>","short":"P. Brighi, D.A. Abanin, M. Serbyn, Physical Review B 102 (2020)."},"publisher":"American Physical Society","department":[{"_id":"MaSe"}],"corr_author":"1","publication_identifier":{"eissn":["2469-9969"],"issn":["2469-9950"]},"isi":1,"status":"public","quality_controlled":"1","scopus_import":"1","OA_type":"green","oa_version":"Preprint","arxiv":1,"issue":"6","day":"26","month":"08"},{"day":"25","month":"11","arxiv":1,"scopus_import":"1","oa_version":"Preprint","quality_controlled":"1","issue":"17","department":[{"_id":"MaSe"}],"citation":{"apa":"Brighi, P., Grilli, M., Leridon, B., &#38; Caprara, S. (2019). Effect of anomalous diffusion of fluctuating Cooper pairs on the density of states of superconducting NbN thin films. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevB.100.174518\">https://doi.org/10.1103/PhysRevB.100.174518</a>","ista":"Brighi P, Grilli M, Leridon B, Caprara S. 2019. Effect of anomalous diffusion of fluctuating Cooper pairs on the density of states of superconducting NbN thin films. Physical Review B. 100(17), 174518.","short":"P. Brighi, M. Grilli, B. Leridon, S. Caprara, Physical Review B 100 (2019).","ama":"Brighi P, Grilli M, Leridon B, Caprara S. Effect of anomalous diffusion of fluctuating Cooper pairs on the density of states of superconducting NbN thin films. <i>Physical Review B</i>. 2019;100(17). doi:<a href=\"https://doi.org/10.1103/PhysRevB.100.174518\">10.1103/PhysRevB.100.174518</a>","ieee":"P. Brighi, M. Grilli, B. Leridon, and S. Caprara, “Effect of anomalous diffusion of fluctuating Cooper pairs on the density of states of superconducting NbN thin films,” <i>Physical Review B</i>, vol. 100, no. 17. American Physical Society, 2019.","chicago":"Brighi, Pietro, Marco Grilli, Brigitte Leridon, and Sergio Caprara. “Effect of Anomalous Diffusion of Fluctuating Cooper Pairs on the Density of States of Superconducting NbN Thin Films.” <i>Physical Review B</i>. American Physical Society, 2019. <a href=\"https://doi.org/10.1103/PhysRevB.100.174518\">https://doi.org/10.1103/PhysRevB.100.174518</a>.","mla":"Brighi, Pietro, et al. “Effect of Anomalous Diffusion of Fluctuating Cooper Pairs on the Density of States of Superconducting NbN Thin Films.” <i>Physical Review B</i>, vol. 100, no. 17, 174518, American Physical Society, 2019, doi:<a href=\"https://doi.org/10.1103/PhysRevB.100.174518\">10.1103/PhysRevB.100.174518</a>."},"publisher":"American Physical Society","date_updated":"2024-02-28T13:14:08Z","status":"public","publication_identifier":{"eissn":["2469-9969"],"issn":["2469-9950"]},"isi":1,"article_processing_charge":"No","external_id":{"arxiv":["1907.13579"],"isi":["000498845700006"]},"author":[{"id":"4115AF5C-F248-11E8-B48F-1D18A9856A87","full_name":"Brighi, Pietro","orcid":"0000-0002-7969-2729","last_name":"Brighi","first_name":"Pietro"},{"first_name":"Marco","full_name":"Grilli, Marco","last_name":"Grilli"},{"first_name":"Brigitte","last_name":"Leridon","full_name":"Leridon, Brigitte"},{"first_name":"Sergio","last_name":"Caprara","full_name":"Caprara, Sergio"}],"volume":100,"date_published":"2019-11-25T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/1907.13579"}],"oa":1,"article_type":"original","publication_status":"published","article_number":"174518","title":"Effect of anomalous diffusion of fluctuating Cooper pairs on the density of states of superconducting NbN thin films","abstract":[{"lang":"eng","text":"Recent scanning tunneling microscopy experiments in NbN thin disordered superconducting films found an emergent inhomogeneity at the scale of tens of nanometers. This inhomogeneity is mirrored by an apparent dimensional crossover in the paraconductivity measured in transport above the superconducting critical temperature Tc. This behavior was interpreted in terms of an anomalous diffusion of fluctuating Cooper pairs that display a quasiconfinement (i.e., a slowing down of their diffusive dynamics) on length scales shorter than the inhomogeneity identified by tunneling experiments. Here, we assume this anomalous diffusive behavior of fluctuating Cooper pairs and calculate the effect of these fluctuations on the electron density of states above Tc. We find that the density of states is substantially suppressed up to temperatures well above Tc. This behavior, which is closely reminiscent of a pseudogap, only arises from the anomalous diffusion of fluctuating Cooper pairs in the absence of stable preformed pairs, setting the stage for an intermediate behavior between the two common paradigms in the superconducting-insulator transition, namely, the localization of Cooper pairs (the so-called bosonic scenario) and the breaking of Cooper pairs into unpaired electrons due to strong disorder (the so-called fermionic scenario)."}],"publication":"Physical Review B","type":"journal_article","_id":"7200","intvolume":"       100","doi":"10.1103/PhysRevB.100.174518","year":"2019","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_created":"2019-12-22T23:00:41Z","language":[{"iso":"eng"}]}]