[{"has_accepted_license":"1","day":"22","citation":{"apa":"Kerschbaumer, A., Ljubotina, M., Serbyn, M., &#38; Desaules, J.-Y. M. (2025). Quantum many-body scars beyond the PXP model in Rydberg simulators. <i>Physical Review Letters</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevLett.134.160401\">https://doi.org/10.1103/PhysRevLett.134.160401</a>","mla":"Kerschbaumer, Aron, et al. “Quantum Many-Body Scars beyond the PXP Model in Rydberg Simulators.” <i>Physical Review Letters</i>, vol. 134, no. 16, 160401, American Physical Society, 2025, doi:<a href=\"https://doi.org/10.1103/PhysRevLett.134.160401\">10.1103/PhysRevLett.134.160401</a>.","short":"A. Kerschbaumer, M. Ljubotina, M. Serbyn, J.-Y.M. Desaules, Physical Review Letters 134 (2025).","ieee":"A. Kerschbaumer, M. Ljubotina, M. Serbyn, and J.-Y. M. Desaules, “Quantum many-body scars beyond the PXP model in Rydberg simulators,” <i>Physical Review Letters</i>, vol. 134, no. 16. American Physical Society, 2025.","chicago":"Kerschbaumer, Aron, Marko Ljubotina, Maksym Serbyn, and Jean-Yves Marc Desaules. “Quantum Many-Body Scars beyond the PXP Model in Rydberg Simulators.” <i>Physical Review Letters</i>. American Physical Society, 2025. <a href=\"https://doi.org/10.1103/PhysRevLett.134.160401\">https://doi.org/10.1103/PhysRevLett.134.160401</a>.","ama":"Kerschbaumer A, Ljubotina M, Serbyn M, Desaules J-YM. Quantum many-body scars beyond the PXP model in Rydberg simulators. <i>Physical Review Letters</i>. 2025;134(16). doi:<a href=\"https://doi.org/10.1103/PhysRevLett.134.160401\">10.1103/PhysRevLett.134.160401</a>","ista":"Kerschbaumer A, Ljubotina M, Serbyn M, Desaules J-YM. 2025. Quantum many-body scars beyond the PXP model in Rydberg simulators. Physical Review Letters. 134(16), 160401."},"abstract":[{"text":"Persistent revivals recently observed in Rydberg atom simulators have challenged our understanding of thermalization and attracted much interest to the concept of quantum many-body scars (QMBSs). QMBSs are non-thermal highly excited eigenstates that coexist with typical eigenstates in the spectrum of many-body Hamiltonians, and have since been reported in multiple theoretical models, including the so-called PXP model, approximately realized by Rydberg simulators. At the same time, questions of how common QMBSs are and in what models they are physically realized remain open. In this Letter, we demonstrate that QMBSs exist in a broader family of models that includes and generalizes PXP to longer-range constraints and states with different periodicity. We show that in each model, multiple QMBS families can be found. Each of them relies on a different approximate algebra, leading to oscillatory dynamics in all cases. However, in contrast to the PXP model, their observation requires launching dynamics from weakly entangled initial states rather than from a product state. QMBSs reported here may be experimentally probed using Rydberg atom simulator in the regime of longer-range Rydberg blockades.","lang":"eng"}],"_id":"19664","language":[{"iso":"eng"}],"external_id":{"pmid":["40344113"],"isi":["001480669300011"],"arxiv":["2410.18913"]},"type":"journal_article","quality_controlled":"1","date_published":"2025-04-22T00:00:00Z","OA_place":"publisher","article_number":"160401","intvolume":"       134","year":"2025","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ddc":["530"],"date_updated":"2025-09-30T12:25:50Z","publication":"Physical Review Letters","isi":1,"file_date_updated":"2025-05-12T07:33:38Z","ec_funded":1,"issue":"16","scopus_import":"1","status":"public","file":[{"date_created":"2025-05-12T07:33:38Z","file_size":1028993,"success":1,"content_type":"application/pdf","access_level":"open_access","file_id":"19677","date_updated":"2025-05-12T07:33:38Z","relation":"main_file","creator":"dernst","file_name":"2025_PhysReviewLetters_Kerschbaumer.pdf","checksum":"b7f581291e20f152d0efc64727314ca2"}],"publication_status":"published","date_created":"2025-05-11T22:02:38Z","title":"Quantum many-body scars beyond the PXP model in Rydberg simulators","oa_version":"Published Version","OA_type":"hybrid","publication_identifier":{"issn":["0031-9007"],"eissn":["1079-7114"]},"arxiv":1,"author":[{"id":"ade85a9c-3200-11ee-973b-91c1eb240410","first_name":"Aron","full_name":"Kerschbaumer, Aron","last_name":"Kerschbaumer"},{"full_name":"Ljubotina, Marko","last_name":"Ljubotina","orcid":"0000-0003-0038-7068","first_name":"Marko","id":"F75EE9BE-5C90-11EA-905D-16643DDC885E"},{"full_name":"Serbyn, Maksym","last_name":"Serbyn","first_name":"Maksym","id":"47809E7E-F248-11E8-B48F-1D18A9856A87","orcid":"0000-0002-2399-5827"},{"full_name":"Desaules, Jean-Yves Marc","last_name":"Desaules","first_name":"Jean-Yves Marc","id":"6c292945-a610-11ed-9eec-c3be1ad62a80","orcid":"0000-0002-3749-6375"}],"volume":134,"project":[{"grant_number":"850899","call_identifier":"H2020","_id":"23841C26-32DE-11EA-91FC-C7463DDC885E","name":"Non-Ergodic Quantum Matter: Universality, Dynamics and Control"},{"_id":"fc2ed2f7-9c52-11eb-aca3-c01059dda49c","call_identifier":"H2020","grant_number":"101034413","name":"IST-BRIDGE: International postdoctoral program"}],"article_type":"original","month":"04","department":[{"_id":"MaSe"}],"acknowledgement":"The authors are grateful to Zlatko Papić, Dolev Bluvstein, Nishad Maskara, Marcello Dalmonte, Thomas Iadecola, and Johannes Feldmeier for insightful discussions. A. K., 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). J.-Y. D. acknowledges funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant Agreement No. 101034413.","oa":1,"doi":"10.1103/PhysRevLett.134.160401","pmid":1,"related_material":{"record":[{"relation":"research_data","status":"public","id":"19623"}]},"tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","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_processing_charge":"Yes (via OA deal)","publisher":"American Physical Society"},{"conference":{"location":"Albuquerque, NM, United States","end_date":"2025-09-05","start_date":"2025-08-30","name":"QCE: International Conference on Quantum Computing and Engineering"},"publication_status":"published","oa_version":"Preprint","OA_type":"green","date_created":"2026-02-17T08:00:17Z","title":"Quantum-guided cluster algorithms for combinatorial optimization","publication_identifier":{"eisbn":["9798331557362"]},"arxiv":1,"month":"09","department":[{"_id":"MaSe"}],"author":[{"first_name":"Peter J.","last_name":"Eder","full_name":"Eder, Peter J."},{"last_name":"Kerschbaumer","full_name":"Kerschbaumer, Aron","orcid":"0009-0002-2370-8661","id":"ade85a9c-3200-11ee-973b-91c1eb240410","first_name":"Aron"},{"last_name":"Finžgar","full_name":"Finžgar, Jernej Rudi","first_name":"Jernej Rudi"},{"orcid":"0000-0002-5383-2869","id":"CE680B90-D85A-11E9-B684-C920E6697425","first_name":"Raimel A","last_name":"Medina Ramos","full_name":"Medina Ramos, Raimel A"},{"last_name":"Schuetz","full_name":"Schuetz, Martin J. A.","first_name":"Martin J. A."},{"first_name":"Helmut G.","last_name":"Katzgraber","full_name":"Katzgraber, Helmut G."},{"first_name":"Sarah","full_name":"Braun, Sarah","last_name":"Braun"},{"first_name":"Christian B.","full_name":"Mendl, Christian B.","last_name":"Mendl"}],"acknowledgement":"P.J.E was partially funded by the German BMWK project QCHALLenge (Grant No. 01MQ22008B).\r\n","doi":"10.1109/qce65121.2025.00033","oa":1,"publisher":"IEEE","corr_author":"1","article_processing_charge":"No","citation":{"ista":"Eder PJ, Kerschbaumer A, Finžgar JR, Medina Ramos RA, Schuetz MJA, Katzgraber HG, Braun S, Mendl CB. 2025. Quantum-guided cluster algorithms for combinatorial optimization. 2025 IEEE International Conference on Quantum Computing and Engineering. QCE: International Conference on Quantum Computing and Engineering.","ama":"Eder PJ, Kerschbaumer A, Finžgar JR, et al. Quantum-guided cluster algorithms for combinatorial optimization. In: <i>2025 IEEE International Conference on Quantum Computing and Engineering</i>. IEEE; 2025. doi:<a href=\"https://doi.org/10.1109/qce65121.2025.00033\">10.1109/qce65121.2025.00033</a>","chicago":"Eder, Peter J., Aron Kerschbaumer, Jernej Rudi Finžgar, Raimel A Medina Ramos, Martin J. A. Schuetz, Helmut G. Katzgraber, Sarah Braun, and Christian B. Mendl. “Quantum-Guided Cluster Algorithms for Combinatorial Optimization.” In <i>2025 IEEE International Conference on Quantum Computing and Engineering</i>. IEEE, 2025. <a href=\"https://doi.org/10.1109/qce65121.2025.00033\">https://doi.org/10.1109/qce65121.2025.00033</a>.","ieee":"P. J. Eder <i>et al.</i>, “Quantum-guided cluster algorithms for combinatorial optimization,” in <i>2025 IEEE International Conference on Quantum Computing and Engineering</i>, Albuquerque, NM, United States, 2025.","short":"P.J. Eder, A. Kerschbaumer, J.R. Finžgar, R.A. Medina Ramos, M.J.A. Schuetz, H.G. Katzgraber, S. Braun, C.B. Mendl, in:, 2025 IEEE International Conference on Quantum Computing and Engineering, IEEE, 2025.","mla":"Eder, Peter J., et al. “Quantum-Guided Cluster Algorithms for Combinatorial Optimization.” <i>2025 IEEE International Conference on Quantum Computing and Engineering</i>, IEEE, 2025, doi:<a href=\"https://doi.org/10.1109/qce65121.2025.00033\">10.1109/qce65121.2025.00033</a>.","apa":"Eder, P. J., Kerschbaumer, A., Finžgar, J. R., Medina Ramos, R. A., Schuetz, M. J. A., Katzgraber, H. G., … Mendl, C. B. (2025). Quantum-guided cluster algorithms for combinatorial optimization. In <i>2025 IEEE International Conference on Quantum Computing and Engineering</i>. Albuquerque, NM, United States: IEEE. <a href=\"https://doi.org/10.1109/qce65121.2025.00033\">https://doi.org/10.1109/qce65121.2025.00033</a>"},"day":"01","type":"conference","quality_controlled":"1","abstract":[{"text":"Finding the ground state of Ising spin glasses is notoriously difficult due to disorder and frustration. Often, this challenge is framed as a combinatorial optimization problem, for which a common strategy employs simulated annealing, a Monte Carlo (MC)-based algorithm that updates spins one at a time. Yet, these localized updates can cause the system to become trapped in local minima. Cluster algorithms (CAs) were developed to address this limitation and have demonstrated considerable success in studying ferromagnetic systems; however, they tend to encounter percolation issues when applied to generic spin glasses. In this work, we introduce a novel CA designed to tackle these challenges by leveraging precomputed two-point correlations, aiming solve combinatorial optimization problems in the form of Max-Cut more efficiently. In our approach, clusters are formed probabilistically based on these correlations. Various classical and quantum algorithms can be employed to generate correlations that embody information about the energy landscape of the problem. By utilizing this information, the algorithm aims to identify groups of spins whose simultaneous flipping induces large transitions in configuration space with high acceptance probability - even at low energy levels - thereby escaping local minima more effectively. Notably, clusters generated using correlations from the Quantum Approximate Optimization Algorithm exhibit high acceptance rates at low temperatures. These acceptance rates often increase with circuit depth, accelerating the algorithm and enabling more efficient exploration of the solution space.","lang":"eng"}],"_id":"21272","language":[{"iso":"eng"}],"external_id":{"arxiv":["2508.10656"]},"main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2508.10656"}],"date_published":"2025-09-01T00:00:00Z","OA_place":"repository","year":"2025","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication":"2025 IEEE International Conference on Quantum Computing and Engineering","date_updated":"2026-02-18T08:45:56Z","status":"public"},{"status":"public","issue":"2","DOAJ_listed":"1","scopus_import":"1","file_date_updated":"2024-05-21T09:35:14Z","publication":"PRX Quantum","date_updated":"2025-05-14T09:29:40Z","intvolume":"         5","article_number":"020327","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","ddc":["530"],"year":"2024","OA_place":"publisher","date_published":"2024-05-01T00:00:00Z","external_id":{"arxiv":["2308.13607"]},"language":[{"iso":"eng"}],"_id":"15407","abstract":[{"lang":"eng","text":"We propose and implement a family of quantum-informed recursive optimization (QIRO) algorithms for combinatorial optimization problems. Our approach leverages quantum resources to obtain information that is used in problem-specific classical reduction steps that recursively simplify the problem. These reduction steps address the limitations of the quantum component (e.g., locality) and ensure solution feasibility in constrained optimization problems. Additionally, we use backtracking techniques to further improve the performance of the algorithm without increasing the requirements on the quantum hardware. We showcase the capabilities of our approach by informing QIRO with correlations from classical simulations of shallow circuits of the quantum approximate optimization algorithm, solving instances of maximum independent set and maximum satisfiability problems with hundreds of variables. We also demonstrate how QIRO can be deployed on a neutral atom quantum processor to find large independent sets of graphs. In summary, our scheme achieves results comparable to classical heuristics even with relatively weak quantum resources. Furthermore, enhancing the quality of these quantum resources improves the performance of the algorithms. Notably, the modular nature of QIRO offers various avenues for modifications, positioning our work as a template for a broader class of hybrid quantum-classical algorithms for combinatorial optimization."}],"quality_controlled":"1","type":"journal_article","day":"01","citation":{"mla":"Finžgar, Jernej Rudi, et al. “Quantum-Informed Recursive Optimization Algorithms.” <i>PRX Quantum</i>, vol. 5, no. 2, 020327, American Physical Society, 2024, doi:<a href=\"https://doi.org/10.1103/PRXQuantum.5.020327\">10.1103/PRXQuantum.5.020327</a>.","ieee":"J. R. Finžgar, A. Kerschbaumer, M. J. A. Schuetz, C. B. Mendl, and H. G. Katzgraber, “Quantum-informed recursive optimization algorithms,” <i>PRX Quantum</i>, vol. 5, no. 2. American Physical Society, 2024.","short":"J.R. Finžgar, A. Kerschbaumer, M.J.A. Schuetz, C.B. Mendl, H.G. Katzgraber, PRX Quantum 5 (2024).","apa":"Finžgar, J. R., Kerschbaumer, A., Schuetz, M. J. A., Mendl, C. B., &#38; Katzgraber, H. G. (2024). Quantum-informed recursive optimization algorithms. <i>PRX Quantum</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PRXQuantum.5.020327\">https://doi.org/10.1103/PRXQuantum.5.020327</a>","ama":"Finžgar JR, Kerschbaumer A, Schuetz MJA, Mendl CB, Katzgraber HG. Quantum-informed recursive optimization algorithms. <i>PRX Quantum</i>. 2024;5(2). doi:<a href=\"https://doi.org/10.1103/PRXQuantum.5.020327\">10.1103/PRXQuantum.5.020327</a>","ista":"Finžgar JR, Kerschbaumer A, Schuetz MJA, Mendl CB, Katzgraber HG. 2024. Quantum-informed recursive optimization algorithms. PRX Quantum. 5(2), 020327.","chicago":"Finžgar, Jernej Rudi, Aron Kerschbaumer, Martin J.A. Schuetz, Christian B. Mendl, and Helmut G. Katzgraber. “Quantum-Informed Recursive Optimization Algorithms.” <i>PRX Quantum</i>. American Physical Society, 2024. <a href=\"https://doi.org/10.1103/PRXQuantum.5.020327\">https://doi.org/10.1103/PRXQuantum.5.020327</a>."},"has_accepted_license":"1","article_processing_charge":"Yes","tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"corr_author":"1","publisher":"American Physical Society","doi":"10.1103/PRXQuantum.5.020327","oa":1,"acknowledgement":"J.R.F. and A.K. thank Libor Caha and Alexander Kliesch for insightful discussions. The authors thank Lilly Palackal, Maximilian Passek, Carlos Riofrío, and Gili Rosenberg for thorough reviews of the manuscript, and the Amazon Braket, BMW, and QuEra teams for their support. C.M. thanks the Munich Quantum Valley initiative, which is supported by the Bavarian State Government with funds from the Hightech Agenda Bayern Plus. H.G.K. would like to thank Am Platzl 1A for providing the necessary environment for creative thinking. An open-source implementation of QIRO is available online [60].","author":[{"first_name":"Jernej Rudi","last_name":"Finžgar","full_name":"Finžgar, Jernej Rudi"},{"full_name":"Kerschbaumer, Aron","last_name":"Kerschbaumer","id":"ade85a9c-3200-11ee-973b-91c1eb240410","first_name":"Aron"},{"last_name":"Schuetz","full_name":"Schuetz, Martin J.A.","first_name":"Martin J.A."},{"full_name":"Mendl, Christian B.","last_name":"Mendl","first_name":"Christian B."},{"full_name":"Katzgraber, Helmut G.","last_name":"Katzgraber","first_name":"Helmut G."}],"volume":5,"month":"05","department":[{"_id":"GradSch"}],"article_type":"original","arxiv":1,"publication_identifier":{"eissn":["2691-3399"]},"date_created":"2024-05-19T22:01:13Z","title":"Quantum-informed recursive optimization algorithms","OA_type":"gold","oa_version":"Published Version","publication_status":"published","file":[{"checksum":"76bdf0b4dc06d59d073a57bd6957a96c","file_name":"2024_PRXQuantum_Finzgar.pdf","date_updated":"2024-05-21T09:35:14Z","file_id":"15409","creator":"dernst","relation":"main_file","access_level":"open_access","success":1,"content_type":"application/pdf","file_size":2016085,"date_created":"2024-05-21T09:35:14Z"}]}]