--- _id: '15002' 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." 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." article_number: '050401' article_processing_charge: No article_type: original author: - first_name: Elena full_name: Petrova, Elena id: 0ac84990-897b-11ed-a09c-f5abb56a4ede last_name: Petrova - first_name: Egor S. full_name: Tiunov, Egor S. last_name: Tiunov - first_name: Mari Carmen full_name: Bañuls, Mari Carmen last_name: Bañuls - first_name: Aleksey K. full_name: Fedorov, Aleksey K. last_name: Fedorov citation: ama: Petrova E, Tiunov ES, Bañuls MC, Fedorov AK. Fractal states of the Schwinger model. Physical Review Letters. 2024;132(5). doi:10.1103/PhysRevLett.132.050401 apa: Petrova, E., Tiunov, E. S., Bañuls, M. C., & Fedorov, A. K. (2024). Fractal states of the Schwinger model. Physical Review Letters. American Physical Society. https://doi.org/10.1103/PhysRevLett.132.050401 chicago: Petrova, Elena, Egor S. Tiunov, Mari Carmen Bañuls, and Aleksey K. Fedorov. “Fractal States of the Schwinger Model.” Physical Review Letters. American Physical Society, 2024. https://doi.org/10.1103/PhysRevLett.132.050401. ieee: E. Petrova, E. S. Tiunov, M. C. Bañuls, and A. K. Fedorov, “Fractal states of the Schwinger model,” Physical Review Letters, vol. 132, no. 5. American Physical Society, 2024. ista: Petrova E, Tiunov ES, Bañuls MC, Fedorov AK. 2024. Fractal states of the Schwinger model. Physical Review Letters. 132(5), 050401. mla: Petrova, Elena, et al. “Fractal States of the Schwinger Model.” Physical Review Letters, vol. 132, no. 5, 050401, American Physical Society, 2024, doi:10.1103/PhysRevLett.132.050401. short: E. Petrova, E.S. Tiunov, M.C. Bañuls, A.K. Fedorov, Physical Review Letters 132 (2024). date_created: 2024-02-18T23:01:00Z date_published: 2024-01-30T00:00:00Z date_updated: 2024-02-26T08:03:31Z day: '30' department: - _id: MaSe doi: 10.1103/PhysRevLett.132.050401 external_id: arxiv: - '2201.10220' intvolume: ' 132' issue: '5' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2201.10220 month: '01' oa: 1 oa_version: Preprint publication: Physical Review Letters publication_identifier: eissn: - 1079-7114 issn: - 0031-9007 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Fractal states of the Schwinger model type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 132 year: '2024' ... --- _id: '15122' abstract: - lang: eng 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. 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. article_number: '013223' article_processing_charge: Yes article_type: original author: - first_name: Stefan full_name: Sack, Stefan id: dd622248-f6e0-11ea-865d-ce382a1c81a5 last_name: Sack orcid: 0000-0001-5400-8508 - first_name: Daniel J. full_name: Egger, Daniel J. last_name: Egger citation: ama: Sack S, Egger DJ. Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation. Physical Review Research. 2024;6(1). doi:10.1103/PhysRevResearch.6.013223 apa: Sack, S., & Egger, D. J. (2024). Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation. Physical Review Research. American Physical Society. https://doi.org/10.1103/PhysRevResearch.6.013223 chicago: Sack, Stefan, and Daniel J. Egger. “Large-Scale Quantum Approximate Optimization on Nonplanar Graphs with Machine Learning Noise Mitigation.” Physical Review Research. American Physical Society, 2024. https://doi.org/10.1103/PhysRevResearch.6.013223. ieee: S. Sack and D. J. Egger, “Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation,” Physical Review Research, vol. 6, no. 1. American Physical Society, 2024. 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. mla: Sack, Stefan, and Daniel J. Egger. “Large-Scale Quantum Approximate Optimization on Nonplanar Graphs with Machine Learning Noise Mitigation.” Physical Review Research, vol. 6, no. 1, 013223, American Physical Society, 2024, doi:10.1103/PhysRevResearch.6.013223. short: S. Sack, D.J. Egger, Physical Review Research 6 (2024). date_created: 2024-03-17T23:00:59Z date_published: 2024-03-01T00:00:00Z date_updated: 2024-03-19T07:24:03Z day: '01' ddc: - '530' department: - _id: MaSe doi: 10.1103/PhysRevResearch.6.013223 external_id: arxiv: - '2307.14427' file: - access_level: open_access checksum: 274c9f1b15b3547a10a03f39e4ccc582 content_type: application/pdf creator: dernst date_created: 2024-03-19T07:16:38Z date_updated: 2024-03-19T07:16:38Z file_id: '15123' file_name: 2024_PhysicalReviewResearch_Sack.pdf file_size: 2777593 relation: main_file success: 1 file_date_updated: 2024-03-19T07:16:38Z has_accepted_license: '1' intvolume: ' 6' issue: '1' language: - iso: eng month: '03' oa: 1 oa_version: Published Version project: - _id: bd660c93-d553-11ed-ba76-fb0fb6f49c0d name: Quantum_Quantum Circuits and Software_Variational quantum algorithms on NISQ devices publication: Physical Review Research publication_identifier: issn: - 2643-1564 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Large-scale quantum approximate optimization on nonplanar graphs with machine learning noise mitigation tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 6 year: '2024' ... --- _id: '13277' abstract: - lang: eng 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. 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. ' article_number: '029' article_processing_charge: No article_type: original author: - first_name: Gennaro full_name: Tucci, Gennaro last_name: Tucci - first_name: Stefano full_name: De Nicola, Stefano id: 42832B76-F248-11E8-B48F-1D18A9856A87 last_name: De Nicola orcid: 0000-0002-4842-6671 - first_name: Sascha full_name: Wald, Sascha last_name: Wald - first_name: Andrea full_name: Gambassi, Andrea last_name: Gambassi citation: ama: Tucci G, De Nicola S, Wald S, Gambassi A. Stochastic representation of the quantum quartic oscillator. SciPost Physics Core. 2023;6(2). doi:10.21468/scipostphyscore.6.2.029 apa: Tucci, G., De Nicola, S., Wald, S., & Gambassi, A. (2023). Stochastic representation of the quantum quartic oscillator. SciPost Physics Core. SciPost Foundation. https://doi.org/10.21468/scipostphyscore.6.2.029 chicago: Tucci, Gennaro, Stefano De Nicola, Sascha Wald, and Andrea Gambassi. “Stochastic Representation of the Quantum Quartic Oscillator.” SciPost Physics Core. SciPost Foundation, 2023. https://doi.org/10.21468/scipostphyscore.6.2.029. ieee: G. Tucci, S. De Nicola, S. Wald, and A. Gambassi, “Stochastic representation of the quantum quartic oscillator,” SciPost Physics Core, vol. 6, no. 2. SciPost Foundation, 2023. ista: Tucci G, De Nicola S, Wald S, Gambassi A. 2023. Stochastic representation of the quantum quartic oscillator. SciPost Physics Core. 6(2), 029. mla: Tucci, Gennaro, et al. “Stochastic Representation of the Quantum Quartic Oscillator.” SciPost Physics Core, vol. 6, no. 2, 029, SciPost Foundation, 2023, doi:10.21468/scipostphyscore.6.2.029. short: G. Tucci, S. De Nicola, S. Wald, A. Gambassi, SciPost Physics Core 6 (2023). date_created: 2023-07-24T10:47:46Z date_published: 2023-04-14T00:00:00Z date_updated: 2023-07-31T09:03:28Z day: '14' ddc: - '530' department: - _id: MaSe doi: 10.21468/scipostphyscore.6.2.029 ec_funded: 1 external_id: arxiv: - '2211.01923' file: - access_level: open_access checksum: b472bc82108747eda5d52adf9e2ac7f3 content_type: application/pdf creator: dernst date_created: 2023-07-31T09:02:27Z date_updated: 2023-07-31T09:02:27Z file_id: '13329' file_name: 2023_SciPostPhysCore_Tucci.pdf file_size: 523236 relation: main_file success: 1 file_date_updated: 2023-07-31T09:02:27Z has_accepted_license: '1' intvolume: ' 6' issue: '2' keyword: - Statistical and Nonlinear Physics - Atomic and Molecular Physics - and Optics - Nuclear and High Energy Physics - Condensed Matter Physics language: - iso: eng month: '04' oa: 1 oa_version: Published Version project: - _id: 260C2330-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '754411' name: ISTplus - Postdoctoral Fellowships publication: SciPost Physics Core publication_identifier: issn: - 2666-9366 publication_status: published publisher: SciPost Foundation quality_controlled: '1' status: public title: Stochastic representation of the quantum quartic oscillator tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 6 year: '2023' ... --- _id: '12790' 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. 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. article_number: '104502' article_processing_charge: No article_type: original author: - first_name: Areg full_name: Ghazaryan, Areg id: 4AF46FD6-F248-11E8-B48F-1D18A9856A87 last_name: Ghazaryan orcid: 0000-0001-9666-3543 - first_name: Tobias full_name: Holder, Tobias last_name: Holder - first_name: Erez full_name: Berg, Erez last_name: Berg - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Ghazaryan A, Holder T, Berg E, Serbyn M. Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity. Physical Review B. 2023;107(10). doi:10.1103/PhysRevB.107.104502 apa: Ghazaryan, A., Holder, T., Berg, E., & Serbyn, M. (2023). Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity. Physical Review B. American Physical Society. https://doi.org/10.1103/PhysRevB.107.104502 chicago: Ghazaryan, Areg, Tobias Holder, Erez Berg, and Maksym Serbyn. “Multilayer Graphenes as a Platform for Interaction-Driven Physics and Topological Superconductivity.” Physical Review B. American Physical Society, 2023. https://doi.org/10.1103/PhysRevB.107.104502. ieee: A. Ghazaryan, T. Holder, E. Berg, and M. Serbyn, “Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity,” Physical Review B, vol. 107, no. 10. American Physical Society, 2023. 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. mla: Ghazaryan, Areg, et al. “Multilayer Graphenes as a Platform for Interaction-Driven Physics and Topological Superconductivity.” Physical Review B, vol. 107, no. 10, 104502, American Physical Society, 2023, doi:10.1103/PhysRevB.107.104502. short: A. Ghazaryan, T. Holder, E. Berg, M. Serbyn, Physical Review B 107 (2023). date_created: 2023-04-02T22:01:10Z date_published: 2023-03-01T00:00:00Z date_updated: 2023-08-01T13:59:29Z day: '01' department: - _id: MaSe - _id: MiLe doi: 10.1103/PhysRevB.107.104502 external_id: arxiv: - '2211.02492' isi: - '000945526400003' intvolume: ' 107' isi: 1 issue: '10' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2211.02492 month: '03' oa: 1 oa_version: Preprint publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' related_material: link: - description: News on the ISTA website relation: press_release url: https://ista.ac.at/en/news/reaching-superconductivity-layer-by-layer/ scopus_import: '1' status: public title: Multilayer graphenes as a platform for interaction-driven physics and topological superconductivity type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 107 year: '2023' ... --- _id: '12839' 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. 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]." article_number: '011033' article_processing_charge: No article_type: original author: - first_name: Marko full_name: Ljubotina, Marko id: F75EE9BE-5C90-11EA-905D-16643DDC885E last_name: Ljubotina - first_name: Jean Yves full_name: Desaules, Jean Yves last_name: Desaules - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 - first_name: Zlatko full_name: Papić, Zlatko last_name: Papić citation: ama: Ljubotina M, Desaules JY, Serbyn M, Papić Z. Superdiffusive energy transport in kinetically constrained models. Physical Review X. 2023;13(1). doi:10.1103/PhysRevX.13.011033 apa: Ljubotina, M., Desaules, J. Y., Serbyn, M., & Papić, Z. (2023). Superdiffusive energy transport in kinetically constrained models. Physical Review X. American Physical Society. https://doi.org/10.1103/PhysRevX.13.011033 chicago: Ljubotina, Marko, Jean Yves Desaules, Maksym Serbyn, and Zlatko Papić. “Superdiffusive Energy Transport in Kinetically Constrained Models.” Physical Review X. American Physical Society, 2023. https://doi.org/10.1103/PhysRevX.13.011033. ieee: M. Ljubotina, J. Y. Desaules, M. Serbyn, and Z. Papić, “Superdiffusive energy transport in kinetically constrained models,” Physical Review X, vol. 13, no. 1. American Physical Society, 2023. ista: Ljubotina M, Desaules JY, Serbyn M, Papić Z. 2023. Superdiffusive energy transport in kinetically constrained models. Physical Review X. 13(1), 011033. mla: Ljubotina, Marko, et al. “Superdiffusive Energy Transport in Kinetically Constrained Models.” Physical Review X, vol. 13, no. 1, 011033, American Physical Society, 2023, doi:10.1103/PhysRevX.13.011033. short: M. Ljubotina, J.Y. Desaules, M. Serbyn, Z. Papić, Physical Review X 13 (2023). date_created: 2023-04-16T22:01:09Z date_published: 2023-03-07T00:00:00Z date_updated: 2023-08-01T14:11:28Z day: '07' ddc: - '530' department: - _id: MaSe doi: 10.1103/PhysRevX.13.011033 ec_funded: 1 external_id: isi: - '000957625700001' file: - access_level: open_access checksum: ee060cea609af79bba7af74b1ce28078 content_type: application/pdf creator: dernst date_created: 2023-04-17T08:36:53Z date_updated: 2023-04-17T08:36:53Z file_id: '12845' file_name: 2023_PhysReviewX_Ljubotina.pdf file_size: 1958523 relation: main_file success: 1 file_date_updated: 2023-04-17T08:36:53Z has_accepted_license: '1' intvolume: ' 13' isi: 1 issue: '1' language: - iso: eng month: '03' oa: 1 oa_version: Published Version project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: Physical Review X publication_identifier: eissn: - 2160-3308 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Superdiffusive energy transport in kinetically constrained models tmp: 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) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 13 year: '2023' ... --- _id: '13963' abstract: - lang: eng 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. 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]." article_number: '054201' article_processing_charge: Yes (in subscription journal) article_type: original author: - first_name: Pietro full_name: Brighi, Pietro id: 4115AF5C-F248-11E8-B48F-1D18A9856A87 last_name: Brighi orcid: 0000-0002-7969-2729 - first_name: Marko full_name: Ljubotina, Marko id: F75EE9BE-5C90-11EA-905D-16643DDC885E last_name: Ljubotina - first_name: Dmitry A. full_name: Abanin, Dmitry A. last_name: Abanin - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Brighi P, Ljubotina M, Abanin DA, Serbyn M. Many-body localization proximity effect in a two-species bosonic Hubbard model. Physical Review B. 2023;108(5). doi:10.1103/physrevb.108.054201 apa: Brighi, P., Ljubotina, M., Abanin, D. A., & Serbyn, M. (2023). Many-body localization proximity effect in a two-species bosonic Hubbard model. Physical Review B. American Physical Society. https://doi.org/10.1103/physrevb.108.054201 chicago: Brighi, Pietro, Marko Ljubotina, Dmitry A. Abanin, and Maksym Serbyn. “Many-Body Localization Proximity Effect in a Two-Species Bosonic Hubbard Model.” Physical Review B. American Physical Society, 2023. https://doi.org/10.1103/physrevb.108.054201. ieee: P. Brighi, M. Ljubotina, D. A. Abanin, and M. Serbyn, “Many-body localization proximity effect in a two-species bosonic Hubbard model,” Physical Review B, vol. 108, no. 5. American Physical Society, 2023. 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. mla: Brighi, Pietro, et al. “Many-Body Localization Proximity Effect in a Two-Species Bosonic Hubbard Model.” Physical Review B, vol. 108, no. 5, 054201, American Physical Society, 2023, doi:10.1103/physrevb.108.054201. short: P. Brighi, M. Ljubotina, D.A. Abanin, M. Serbyn, Physical Review B 108 (2023). date_created: 2023-08-05T18:25:22Z date_published: 2023-08-01T00:00:00Z date_updated: 2023-08-07T09:51:39Z day: '01' ddc: - '530' department: - _id: MaSe doi: 10.1103/physrevb.108.054201 ec_funded: 1 external_id: arxiv: - '2303.16876' file: - access_level: open_access checksum: f763000339b5fd543c14377109920690 content_type: application/pdf creator: dernst date_created: 2023-08-07T09:48:08Z date_updated: 2023-08-07T09:48:08Z file_id: '13981' file_name: 2023_PhysRevB_Brighi.pdf file_size: 3051398 relation: main_file success: 1 file_date_updated: 2023-08-07T09:48:08Z has_accepted_license: '1' intvolume: ' 108' issue: '5' language: - iso: eng month: '08' oa: 1 oa_version: Published Version project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Many-body localization proximity effect in a two-species bosonic Hubbard model tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 108 year: '2023' ... --- _id: '14320' abstract: - lang: eng text: The development of two-dimensional materials has resulted in a diverse range of novel, high-quality compounds with increasing complexity. A key requirement for a comprehensive quantitative theory is the accurate determination of these materials' band structure parameters. However, this task is challenging due to the intricate band structures and the indirect nature of experimental probes. In this work, we introduce a general framework to derive band structure parameters from experimental data using deep neural networks. We applied our method to the penetration field capacitance measurement of trilayer graphene, an effective probe of its density of states. First, we demonstrate that a trained deep network gives accurate predictions for the penetration field capacitance as a function of tight-binding parameters. Next, we use the fast and accurate predictions from the trained network to automatically determine tight-binding parameters directly from experimental data, with extracted parameters being in a good agreement with values in the literature. We conclude by discussing potential applications of our method to other materials and experimental techniques beyond penetration field capacitance. acknowledgement: A.F.Y. acknowledges primary support from the Department of Energy under award DE-SC0020043, and additional support from the Gordon and Betty Moore Foundation under award GBMF9471 for group operations. article_number: '125411' article_processing_charge: No article_type: original author: - first_name: Paul M full_name: Henderson, Paul M id: 13C09E74-18D9-11E9-8878-32CFE5697425 last_name: Henderson orcid: 0000-0002-5198-7445 - first_name: Areg full_name: Ghazaryan, Areg id: 4AF46FD6-F248-11E8-B48F-1D18A9856A87 last_name: Ghazaryan orcid: 0000-0001-9666-3543 - first_name: Alexander A. full_name: Zibrov, Alexander A. last_name: Zibrov - first_name: Andrea F. full_name: Young, Andrea F. last_name: Young - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: 'Henderson PM, Ghazaryan A, Zibrov AA, Young AF, Serbyn M. Deep learning extraction of band structure parameters from density of states: A case study on trilayer graphene. Physical Review B. 2023;108(12). doi:10.1103/physrevb.108.125411' apa: 'Henderson, P. M., Ghazaryan, A., Zibrov, A. A., Young, A. F., & Serbyn, M. (2023). Deep learning extraction of band structure parameters from density of states: A case study on trilayer graphene. Physical Review B. American Physical Society. https://doi.org/10.1103/physrevb.108.125411' chicago: 'Henderson, Paul M, Areg Ghazaryan, Alexander A. Zibrov, Andrea F. Young, and Maksym Serbyn. “Deep Learning Extraction of Band Structure Parameters from Density of States: A Case Study on Trilayer Graphene.” Physical Review B. American Physical Society, 2023. https://doi.org/10.1103/physrevb.108.125411.' ieee: 'P. M. Henderson, A. Ghazaryan, A. A. Zibrov, A. F. Young, and M. Serbyn, “Deep learning extraction of band structure parameters from density of states: A case study on trilayer graphene,” Physical Review B, vol. 108, no. 12. American Physical Society, 2023.' ista: 'Henderson PM, Ghazaryan A, Zibrov AA, Young AF, Serbyn M. 2023. Deep learning extraction of band structure parameters from density of states: A case study on trilayer graphene. Physical Review B. 108(12), 125411.' mla: 'Henderson, Paul M., et al. “Deep Learning Extraction of Band Structure Parameters from Density of States: A Case Study on Trilayer Graphene.” Physical Review B, vol. 108, no. 12, 125411, American Physical Society, 2023, doi:10.1103/physrevb.108.125411.' short: P.M. Henderson, A. Ghazaryan, A.A. Zibrov, A.F. Young, M. Serbyn, Physical Review B 108 (2023). date_created: 2023-09-12T07:12:12Z date_published: 2023-09-15T00:00:00Z date_updated: 2023-09-20T09:38:24Z day: '15' department: - _id: MaSe - _id: ChLa - _id: MiLe doi: 10.1103/physrevb.108.125411 external_id: arxiv: - '2210.06310' intvolume: ' 108' issue: '12' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2210.06310 month: '09' oa: 1 oa_version: Preprint publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: 'Deep learning extraction of band structure parameters from density of states: A case study on trilayer graphene' type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 108 year: '2023' ... --- _id: '12732' 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." acknowledged_ssus: - _id: ScienComp alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Pietro full_name: Brighi, Pietro id: 4115AF5C-F248-11E8-B48F-1D18A9856A87 last_name: Brighi orcid: 0000-0002-7969-2729 citation: ama: Brighi P. Ergodicity breaking in disordered and kinetically constrained quantum many-body systems. 2023. doi:10.15479/at:ista:12732 apa: Brighi, P. (2023). Ergodicity breaking in disordered and kinetically constrained quantum many-body systems. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12732 chicago: Brighi, Pietro. “Ergodicity Breaking in Disordered and Kinetically Constrained Quantum Many-Body Systems.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12732. ieee: P. Brighi, “Ergodicity breaking in disordered and kinetically constrained quantum many-body systems,” Institute of Science and Technology Austria, 2023. ista: Brighi P. 2023. Ergodicity breaking in disordered and kinetically constrained quantum many-body systems. Institute of Science and Technology Austria. mla: Brighi, Pietro. Ergodicity Breaking in Disordered and Kinetically Constrained Quantum Many-Body Systems. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12732. short: P. Brighi, Ergodicity Breaking in Disordered and Kinetically Constrained Quantum Many-Body Systems, Institute of Science and Technology Austria, 2023. date_created: 2023-03-17T13:30:48Z date_published: 2023-03-21T00:00:00Z date_updated: 2023-09-20T10:44:12Z day: '21' ddc: - '530' degree_awarded: PhD department: - _id: GradSch - _id: MaSe doi: 10.15479/at:ista:12732 ec_funded: 1 file: - access_level: closed checksum: 5d2de651ef9449c1b8dc27148ca74777 content_type: application/zip creator: pbrighi date_created: 2023-03-23T16:42:56Z date_updated: 2023-03-23T16:42:56Z file_id: '12753' file_name: Thesis_sub_PBrighi.zip file_size: 42167561 relation: source_file - access_level: open_access checksum: 7caa153d4a5b0873a79358787d2dfe1e content_type: application/pdf creator: pbrighi date_created: 2023-03-23T16:43:14Z date_updated: 2023-03-23T16:43:14Z file_id: '12754' file_name: Thesis_PBrighi.pdf file_size: 13977000 relation: main_file success: 1 file_date_updated: 2023-03-23T16:43:14Z has_accepted_license: '1' language: - iso: eng month: '03' oa: 1 oa_version: None page: '158' project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11470' relation: part_of_dissertation status: public - id: '8308' relation: part_of_dissertation status: public - id: '11469' relation: part_of_dissertation status: public - id: '12750' relation: part_of_dissertation status: public status: public supervisor: - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 title: Ergodicity breaking in disordered and kinetically constrained quantum many-body systems tmp: image: /images/cc_by_nc_sa.png legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) short: CC BY-NC-SA (4.0) type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '14334' 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 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. 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)." article_number: '093' article_processing_charge: No article_type: original author: - first_name: Pietro full_name: Brighi, Pietro id: 4115AF5C-F248-11E8-B48F-1D18A9856A87 last_name: Brighi orcid: 0000-0002-7969-2729 - first_name: Marko full_name: Ljubotina, Marko id: F75EE9BE-5C90-11EA-905D-16643DDC885E last_name: Ljubotina orcid: 0000-0003-0038-7068 - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Brighi P, Ljubotina M, Serbyn M. Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. SciPost Physics. 2023;15(3). doi:10.21468/scipostphys.15.3.093 apa: Brighi, P., Ljubotina, M., & Serbyn, M. (2023). Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models. SciPost Physics. SciPost Foundation. https://doi.org/10.21468/scipostphys.15.3.093 chicago: Brighi, Pietro, Marko Ljubotina, and Maksym Serbyn. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving Quantum East Models.” SciPost Physics. SciPost Foundation, 2023. https://doi.org/10.21468/scipostphys.15.3.093. ieee: P. Brighi, M. Ljubotina, and M. Serbyn, “Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models,” SciPost Physics, vol. 15, no. 3. SciPost Foundation, 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. mla: Brighi, Pietro, et al. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving Quantum East Models.” SciPost Physics, vol. 15, no. 3, 093, SciPost Foundation, 2023, doi:10.21468/scipostphys.15.3.093. short: P. Brighi, M. Ljubotina, M. Serbyn, SciPost Physics 15 (2023). date_created: 2023-09-14T13:08:23Z date_published: 2023-09-13T00:00:00Z date_updated: 2023-09-20T10:46:29Z day: '13' ddc: - '530' department: - _id: MaSe doi: 10.21468/scipostphys.15.3.093 ec_funded: 1 external_id: arxiv: - '2210.15607' file: - access_level: open_access checksum: 4cef6a8021f6b6c47ab2f2f2b1387ac2 content_type: application/pdf creator: dernst date_created: 2023-09-20T10:46:10Z date_updated: 2023-09-20T10:46:10Z file_id: '14350' file_name: 2023_SciPostPhysics_Brighi.pdf file_size: 4866506 relation: main_file success: 1 file_date_updated: 2023-09-20T10:46:10Z has_accepted_license: '1' intvolume: ' 15' issue: '3' keyword: - General Physics and Astronomy language: - iso: eng month: '09' oa: 1 oa_version: Published Version project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: SciPost Physics publication_identifier: issn: - 2542-4653 publication_status: published publisher: SciPost Foundation quality_controlled: '1' related_material: record: - id: '12750' relation: earlier_version status: public status: public title: Hilbert space fragmentation and slow dynamics in particle-conserving quantum East models tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 15 year: '2023' ... --- _id: '14406' abstract: - lang: eng text: "Recently, a concept of generalized multifractality, which characterizes fluctuations and correlations of critical eigenstates, was introduced and explored for all 10 symmetry classes of disordered systems. Here, by using the nonlinear sigma-model (\r\nNL\r\nσ\r\nM\r\n) field theory, we extend the theory of generalized multifractality to boundaries of systems at criticality. Our numerical simulations on two-dimensional systems of symmetry classes A, C, and AII fully confirm the analytical predictions of pure-scaling observables and Weyl symmetry relations between critical exponents of surface generalized multifractality. This demonstrates the validity of the \r\nNL\r\nσ\r\nM\r\n for the description of Anderson-localization critical phenomena, not only in the bulk but also on the boundary. The critical exponents strongly violate generalized parabolicity, in analogy with earlier results for the bulk, corroborating the conclusion that the considered Anderson-localization critical points are not described by conformal field theories. We further derive relations between generalized surface multifractal spectra and linear combinations of Lyapunov exponents of a strip in quasi-one-dimensional geometry, which hold under the assumption of invariance with respect to a logarithmic conformal map. Our numerics demonstrate that these relations hold with an excellent accuracy. Taken together, our results indicate an intriguing situation: the conformal invariance is broken but holds partially at critical points of Anderson localization." acknowledgement: "We thank Ilya Gruzberg for many illuminating discussions. S.S.B., J.F.K., and A.D.M. acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) via the Grant\r\nNo. MI 658/14-1. I.S.B. acknowledges support from Russian Science Foundation (Grant No. 22-42-04416)." article_number: '104205' article_processing_charge: No article_type: original author: - first_name: Serafim full_name: Babkin, Serafim id: 41e64307-6672-11ee-b9ad-cc7a0075a479 last_name: Babkin orcid: 0009-0003-7382-8036 - first_name: Jonas F. full_name: Karcher, Jonas F. last_name: Karcher - first_name: Igor S. full_name: Burmistrov, Igor S. last_name: Burmistrov - first_name: Alexander D. full_name: Mirlin, Alexander D. last_name: Mirlin citation: ama: Babkin S, Karcher JF, Burmistrov IS, Mirlin AD. Generalized surface multifractality in two-dimensional disordered systems. Physical Review B. 2023;108(10). doi:10.1103/PhysRevB.108.104205 apa: Babkin, S., Karcher, J. F., Burmistrov, I. S., & Mirlin, A. D. (2023). Generalized surface multifractality in two-dimensional disordered systems. Physical Review B. American Physical Society. https://doi.org/10.1103/PhysRevB.108.104205 chicago: Babkin, Serafim, Jonas F. Karcher, Igor S. Burmistrov, and Alexander D. Mirlin. “Generalized Surface Multifractality in Two-Dimensional Disordered Systems.” Physical Review B. American Physical Society, 2023. https://doi.org/10.1103/PhysRevB.108.104205. ieee: S. Babkin, J. F. Karcher, I. S. Burmistrov, and A. D. Mirlin, “Generalized surface multifractality in two-dimensional disordered systems,” Physical Review B, vol. 108, no. 10. American Physical Society, 2023. ista: Babkin S, Karcher JF, Burmistrov IS, Mirlin AD. 2023. Generalized surface multifractality in two-dimensional disordered systems. Physical Review B. 108(10), 104205. mla: Babkin, Serafim, et al. “Generalized Surface Multifractality in Two-Dimensional Disordered Systems.” Physical Review B, vol. 108, no. 10, 104205, American Physical Society, 2023, doi:10.1103/PhysRevB.108.104205. short: S. Babkin, J.F. Karcher, I.S. Burmistrov, A.D. Mirlin, Physical Review B 108 (2023). date_created: 2023-10-08T22:01:17Z date_published: 2023-09-01T00:00:00Z date_updated: 2023-10-09T07:09:30Z day: '01' department: - _id: MaSe doi: 10.1103/PhysRevB.108.104205 external_id: arxiv: - '2306.09455' intvolume: ' 108' issue: '10' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2306.09455 month: '09' oa: 1 oa_version: Preprint publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Generalized surface multifractality in two-dimensional disordered systems type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 108 year: '2023' ... --- _id: '13125' abstract: - lang: eng text: 'The quantum approximate optimization algorithm (QAOA) is a variational quantum algorithm, where a quantum computer implements a variational ansatz consisting of p layers of alternating unitary operators and a classical computer is used to optimize the variational parameters. For a random initialization, the optimization typically leads to local minima with poor performance, motivating the search for initialization strategies of QAOA variational parameters. Although numerous heuristic initializations exist, an analytical understanding and performance guarantees for large p remain evasive.We introduce a greedy initialization of QAOA which guarantees improving performance with an increasing number of layers. Our main result is an analytic construction of 2p + 1 transition states—saddle points with a unique negative curvature direction—for QAOA with p + 1 layers that use the local minimum of QAOA with p layers. Transition states connect to new local minima, which are guaranteed to lower the energy compared to the minimum found for p layers. We use the GREEDY procedure to navigate the exponentially increasing with p number of local minima resulting from the recursive application of our analytic construction. The performance of the GREEDY procedure matches available initialization strategies while providing a guarantee for the minimal energy to decrease with an increasing number of layers p. ' acknowledgement: 'We thank V. Verteletskyi for a joint collaboration on numerical studies of the QAOA during his internship at ISTA that inspired analytic results on TS reported in this work. We acknowledge A. A. Mele and M. Brooks for discussions and D. Egger, P. Love, and D. Wierichs for valuable feedback on the manuscript. S.H.S., R.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). R.K. is supported by the SFB BeyondC (Grant No. F7107-N38) and the project QuantumReady (FFG 896217). ' article_number: '062404' article_processing_charge: No article_type: original author: - first_name: Stefan full_name: Sack, Stefan id: dd622248-f6e0-11ea-865d-ce382a1c81a5 last_name: Sack orcid: 0000-0001-5400-8508 - first_name: Raimel A full_name: Medina Ramos, Raimel A id: CE680B90-D85A-11E9-B684-C920E6697425 last_name: Medina Ramos orcid: 0000-0002-5383-2869 - first_name: Richard full_name: Kueng, Richard last_name: Kueng - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Sack S, Medina Ramos RA, Kueng R, Serbyn M. Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement. Physical Review A. 2023;107(6). doi:10.1103/physreva.107.062404 apa: Sack, S., Medina Ramos, R. A., Kueng, R., & Serbyn, M. (2023). Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement. Physical Review A. American Physical Society. https://doi.org/10.1103/physreva.107.062404 chicago: Sack, Stefan, Raimel A Medina Ramos, Richard Kueng, and Maksym Serbyn. “Recursive Greedy Initialization of the Quantum Approximate Optimization Algorithm with Guaranteed Improvement.” Physical Review A. American Physical Society, 2023. https://doi.org/10.1103/physreva.107.062404. ieee: S. Sack, R. A. Medina Ramos, R. Kueng, and M. Serbyn, “Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement,” Physical Review A, vol. 107, no. 6. American Physical Society, 2023. ista: Sack S, Medina Ramos RA, Kueng R, Serbyn M. 2023. Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement. Physical Review A. 107(6), 062404. mla: Sack, Stefan, et al. “Recursive Greedy Initialization of the Quantum Approximate Optimization Algorithm with Guaranteed Improvement.” Physical Review A, vol. 107, no. 6, 062404, American Physical Society, 2023, doi:10.1103/physreva.107.062404. short: S. Sack, R.A. Medina Ramos, R. Kueng, M. Serbyn, Physical Review A 107 (2023). date_created: 2023-06-07T06:57:32Z date_published: 2023-06-02T00:00:00Z date_updated: 2023-12-13T14:47:25Z day: '02' ddc: - '530' department: - _id: MaSe doi: 10.1103/physreva.107.062404 ec_funded: 1 external_id: arxiv: - '2209.01159' isi: - '001016927100012' file: - access_level: open_access checksum: 0d71423888eeccaa60d8f41197f26306 content_type: application/pdf creator: dernst date_created: 2023-06-13T07:28:36Z date_updated: 2023-06-13T07:28:36Z file_id: '13131' file_name: 2023_PhysRevA_Sack.pdf file_size: 2524611 relation: main_file success: 1 file_date_updated: 2023-06-13T07:28:36Z has_accepted_license: '1' intvolume: ' 107' isi: 1 issue: '6' language: - iso: eng month: '06' oa: 1 oa_version: Published Version project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: Physical Review A publication_identifier: eissn: - 2469-9934 issn: - 2469-9926 publication_status: published publisher: American Physical Society quality_controlled: '1' related_material: record: - id: '14622' relation: dissertation_contains status: public scopus_import: '1' status: public title: Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement tmp: 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) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 107 year: '2023' ... --- _id: '14622' alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Stefan full_name: Sack, Stefan id: dd622248-f6e0-11ea-865d-ce382a1c81a5 last_name: Sack orcid: 0000-0001-5400-8508 citation: ama: 'Sack S. Improving variational quantum algorithms: Innovative initialization techniques and extensions to qudit systems. 2023. doi:10.15479/at:ista:14622' apa: 'Sack, S. (2023). Improving variational quantum algorithms: Innovative initialization techniques and extensions to qudit systems. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14622' chicago: 'Sack, Stefan. “Improving Variational Quantum Algorithms: Innovative Initialization Techniques and Extensions to Qudit Systems.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14622.' ieee: 'S. Sack, “Improving variational quantum algorithms: Innovative initialization techniques and extensions to qudit systems,” Institute of Science and Technology Austria, 2023.' ista: 'Sack S. 2023. Improving variational quantum algorithms: Innovative initialization techniques and extensions to qudit systems. Institute of Science and Technology Austria.' mla: 'Sack, Stefan. Improving Variational Quantum Algorithms: Innovative Initialization Techniques and Extensions to Qudit Systems. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14622.' short: 'S. Sack, Improving Variational Quantum Algorithms: Innovative Initialization Techniques and Extensions to Qudit Systems, Institute of Science and Technology Austria, 2023.' date_created: 2023-11-28T10:58:13Z date_published: 2023-11-30T00:00:00Z date_updated: 2023-12-13T14:47:25Z day: '30' ddc: - '530' degree_awarded: PhD department: - _id: GradSch - _id: MaSe doi: 10.15479/at:ista:14622 ec_funded: 1 file: - access_level: closed checksum: 068fd3570506ec42b2faa390de784bc4 content_type: application/pdf creator: ssack date_created: 2023-11-30T15:53:10Z date_updated: 2023-12-01T11:10:46Z embargo: 2024-11-30 embargo_to: open_access file_id: '14635' file_name: PhD_Thesis.pdf file_size: 11947523 relation: main_file - access_level: closed checksum: 0fa3bc0d108aed0ac59d2c6beef2220a content_type: application/zip creator: ssack date_created: 2023-11-30T15:54:11Z date_updated: 2023-12-01T11:10:46Z file_id: '14636' file_name: PhD Thesis (1).zip file_size: 18422964 relation: source_file file_date_updated: 2023-12-01T11:10:46Z has_accepted_license: '1' language: - iso: eng month: '11' oa_version: Published Version page: '142' project: - _id: bd660c93-d553-11ed-ba76-fb0fb6f49c0d name: Quantum_Quantum Circuits and Software_Variational quantum algorithms on NISQ devices - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication_identifier: issn: - 2663 - 337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11471' relation: part_of_dissertation status: public - id: '13125' relation: part_of_dissertation status: public - id: '9760' relation: part_of_dissertation status: public status: public supervisor: - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 title: 'Improving variational quantum algorithms: Innovative initialization techniques and extensions to qudit systems' tmp: image: /images/cc_by_nc_sa.png legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) short: CC BY-NC-SA (4.0) type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '14690' abstract: - lang: eng text: Generalized multifractality characterizes system size dependence of pure scaling local observables at Anderson transitions in all 10 symmetry classes of disordered systems. Recently, the concept of generalized multifractality has been extended to boundaries of critical disordered noninteracting systems. Here we study the generalized boundary multifractality in the presence of electron-electron interaction, focusing on the spin quantum Hall symmetry class (class C). Employing the two-loop renormalization group analysis within the Finkel'stein nonlinear sigma model, we compute the anomalous dimensions of the pure scaling operators located at the boundary of the system. We find that generalized boundary multifractal exponents are twice larger than their bulk counterparts. Exact symmetry relations between generalized boundary multifractal exponents in the case of noninteracting systems are explicitly broken by the interaction. acknowledgement: The authors are grateful to J. Karcher and A. Mirlin for collaboration on the related project. We thank I. Gruzberg and A. Mirlin for useful discussions and comments. I.S.B. is grateful to M. Parfenov and P. Ostrovsky for collaboration on the related project. The research was supported by Russian Science Foundation (Grant No. 22-42-04416). article_number: '205429' article_processing_charge: No article_type: original author: - first_name: Serafim full_name: Babkin, Serafim id: 41e64307-6672-11ee-b9ad-cc7a0075a479 last_name: Babkin orcid: 0009-0003-7382-8036 - first_name: I full_name: Burmistrov, I last_name: Burmistrov citation: ama: Babkin S, Burmistrov I. Boundary multifractality in the spin quantum Hall symmetry class with interaction. Physical Review B. 2023;108(20). doi:10.1103/PhysRevB.108.205429 apa: Babkin, S., & Burmistrov, I. (2023). Boundary multifractality in the spin quantum Hall symmetry class with interaction. Physical Review B. American Physical Society. https://doi.org/10.1103/PhysRevB.108.205429 chicago: Babkin, Serafim, and I Burmistrov. “Boundary Multifractality in the Spin Quantum Hall Symmetry Class with Interaction.” Physical Review B. American Physical Society, 2023. https://doi.org/10.1103/PhysRevB.108.205429. ieee: S. Babkin and I. Burmistrov, “Boundary multifractality in the spin quantum Hall symmetry class with interaction,” Physical Review B, vol. 108, no. 20. American Physical Society, 2023. ista: Babkin S, Burmistrov I. 2023. Boundary multifractality in the spin quantum Hall symmetry class with interaction. Physical Review B. 108(20), 205429. mla: Babkin, Serafim, and I. Burmistrov. “Boundary Multifractality in the Spin Quantum Hall Symmetry Class with Interaction.” Physical Review B, vol. 108, no. 20, 205429, American Physical Society, 2023, doi:10.1103/PhysRevB.108.205429. short: S. Babkin, I. Burmistrov, Physical Review B 108 (2023). date_created: 2023-12-17T23:00:53Z date_published: 2023-11-15T00:00:00Z date_updated: 2023-12-18T08:45:28Z day: '15' department: - _id: MaSe doi: 10.1103/PhysRevB.108.205429 external_id: arxiv: - '2308.16852' intvolume: ' 108' issue: '20' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2308.16852' month: '11' oa: 1 oa_version: Preprint publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Boundary multifractality in the spin quantum Hall symmetry class with interaction type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 108 year: '2023' ... --- _id: '10769' abstract: - lang: eng text: studiamos aspectos de Teoría Cuántica de Campos a densidad finita usando técnicas y conceptos de información cuántica. Nos enfocamos en fermiones de Dirac masivos con potencial químico en 1+1 dimensiones espacio-temporales. Usando la entropía de entrelazamiento en un intervalo, construimos la función c entrópica que es finita. Esta función c no es monótona, e incorpora el entrelazamiento de largo alcance proveniente de la superficie de Fermi. Motivados por trabajos previos de modelos en la red, calculamos numéricamente las entropías de Renyi y encontramos oscilaciones de Friedel. Seguidamente, analizamos la información mutua como una medida de correlación entre diferentes regiones. Usando una expansión de distancia grande desarrollada por Cardy, argumentamos que la información mutua detecta las correlaciones inducidas por la superficie de Fermi todavía al orden dominante en la expansión. Finalmente, analizamos la entropía relativa y sus generalizaciones de Renyi para distinguir estados con diferente carga. Encontramos que estados en diferentes sectores de superselección dan origen a un comportamiento super-extensivo en la entropía relativa. acknowledgement: "Se agradece a Horacio Casini por distintas discusiones y comentarios a lo largo del trabajo. LD cuenta con el apoyo de CNEA y UNCuyo, Inst. GT cuenta con el apoyo de CONICET,\r\nANPCyT, CNEA, y UNCuyo, Inst. Balseiro. RM cuenta con el apoyo de IST Austria. MS cuenta con el apoyode CONICET y UNCuyo, Inst. Balseiro. También se agradece a la Asociación Argentina de Física por la posibilidad de presentar este artículo en el marco de una Mención Especial por el Premio Luis Másperi 2020." article_processing_charge: No article_type: original author: - first_name: L. full_name: Daguerre, L. last_name: Daguerre - first_name: G. full_name: Torroba, G. last_name: Torroba - first_name: Raimel A full_name: Medina Ramos, Raimel A id: CE680B90-D85A-11E9-B684-C920E6697425 last_name: Medina Ramos - first_name: M. full_name: Solís, M. last_name: Solís citation: ama: 'Daguerre L, Torroba G, Medina Ramos RA, Solís M. Non relativistic quantum field theory: Dynamics and irreversibility. Anales de la Asociacion Fisica Argentina. 2022;32(4):93-98. doi:10.31527/analesafa.2021.32.4.93' apa: 'Daguerre, L., Torroba, G., Medina Ramos, R. A., & Solís, M. (2022). Non relativistic quantum field theory: Dynamics and irreversibility. Anales de la Asociacion Fisica Argentina. Asociación Física Argentina. https://doi.org/10.31527/analesafa.2021.32.4.93' chicago: 'Daguerre, L., G. Torroba, Raimel A Medina Ramos, and M. Solís. “Non relativistic quantum field theory: Dynamics and irreversibility.” Anales de la Asociacion Fisica Argentina. Asociación Física Argentina, 2022. https://doi.org/10.31527/analesafa.2021.32.4.93.' ieee: 'L. Daguerre, G. Torroba, R. A. Medina Ramos, and M. Solís, “Non relativistic quantum field theory: Dynamics and irreversibility,” Anales de la Asociacion Fisica Argentina, vol. 32, no. 4. Asociación Física Argentina, pp. 93–98, 2022.' ista: 'Daguerre L, Torroba G, Medina Ramos RA, Solís M. 2022. Non relativistic quantum field theory: Dynamics and irreversibility. Anales de la Asociacion Fisica Argentina. 32(4), 93–98.' mla: 'Daguerre, L., et al. “Non relativistic quantum field theory: Dynamics and irreversibility.” Anales de la Asociacion Fisica Argentina, vol. 32, no. 4, Asociación Física Argentina, 2022, pp. 93–98, doi:10.31527/analesafa.2021.32.4.93.' short: L. Daguerre, G. Torroba, R.A. Medina Ramos, M. Solís, Anales de la Asociacion Fisica Argentina 32 (2022) 93–98. date_created: 2022-02-20T23:01:32Z date_published: 2022-01-13T00:00:00Z date_updated: 2022-02-21T09:36:01Z day: '13' ddc: - '530' department: - _id: MaSe doi: 10.31527/analesafa.2021.32.4.93 file: - access_level: open_access checksum: ca66a3017205677c5b4d22b3bb74fb0b content_type: application/pdf creator: dernst date_created: 2022-02-21T09:32:44Z date_updated: 2022-02-21T09:32:44Z file_id: '10782' file_name: 2022_AnalesAFA_Daguerre.pdf file_size: 4505751 relation: main_file success: 1 file_date_updated: 2022-02-21T09:32:44Z has_accepted_license: '1' intvolume: ' 32' issue: '4' language: - iso: spa month: '01' oa: 1 oa_version: Published Version page: 93-98 publication: Anales de la Asociacion Fisica Argentina publication_identifier: eissn: - '18501168' publication_status: published publisher: Asociación Física Argentina quality_controlled: '1' scopus_import: '1' status: public title: 'Non relativistic quantum field theory: Dynamics and irreversibility' tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 32 year: '2022' ... --- _id: '12111' abstract: - lang: eng text: Quantum impurities exhibit fascinating many-body phenomena when the small interacting impurity changes the physics of a large noninteracting environment. The characterisation of such strongly correlated nonperturbative effects is particularly challenging due to the infinite size of the environment, and the inability of local correlators to capture the buildup of long-ranged entanglement in the system. Here, we harness an entanglement-based observable—the purity of the impurity—as a witness for the formation of strong correlations. We showcase the utility of our scheme by exactly solving the open Kondo box model in the small box limit, and thus describe all-electronic dot-cavity devices. Specifically, we conclusively characterize the metal-to-insulator phase transition in the system and identify how the (conducting) dot-lead Kondo singlet is quenched by an (insulating) intraimpurity singlet formation. Furthermore, we propose an experimentally feasible tomography protocol for the measurement of the purity, which motivates the observation of impurity physics through their entanglement build up. acknowledgement: We thank G. Blatter, T. Ihn, K. Ensslin, M. Goldstein, C. Carisch, and J. del Pino for illuminating discussions and acknowledge financial support from the Swiss National Science Foundation (SNSF) through Project No. 190078, and from the Deutsche Forschungsgemeinschaft (DFG) - Project No. 449653034. Our numerical implementations are based on the ITensors JULIA library [64]. article_number: '043177' article_processing_charge: No article_type: original author: - first_name: Lidia full_name: Stocker, Lidia last_name: Stocker - first_name: Stefan full_name: Sack, Stefan id: dd622248-f6e0-11ea-865d-ce382a1c81a5 last_name: Sack - first_name: Michael S. full_name: Ferguson, Michael S. last_name: Ferguson - first_name: Oded full_name: Zilberberg, Oded last_name: Zilberberg citation: ama: Stocker L, Sack S, Ferguson MS, Zilberberg O. Entanglement-based observables for quantum impurities. Physical Review Research. 2022;4(4). doi:10.1103/PhysRevResearch.4.043177 apa: Stocker, L., Sack, S., Ferguson, M. S., & Zilberberg, O. (2022). Entanglement-based observables for quantum impurities. Physical Review Research. American Physical Society. https://doi.org/10.1103/PhysRevResearch.4.043177 chicago: Stocker, Lidia, Stefan Sack, Michael S. Ferguson, and Oded Zilberberg. “Entanglement-Based Observables for Quantum Impurities.” Physical Review Research. American Physical Society, 2022. https://doi.org/10.1103/PhysRevResearch.4.043177. ieee: L. Stocker, S. Sack, M. S. Ferguson, and O. Zilberberg, “Entanglement-based observables for quantum impurities,” Physical Review Research, vol. 4, no. 4. American Physical Society, 2022. ista: Stocker L, Sack S, Ferguson MS, Zilberberg O. 2022. Entanglement-based observables for quantum impurities. Physical Review Research. 4(4), 043177. mla: Stocker, Lidia, et al. “Entanglement-Based Observables for Quantum Impurities.” Physical Review Research, vol. 4, no. 4, 043177, American Physical Society, 2022, doi:10.1103/PhysRevResearch.4.043177. short: L. Stocker, S. Sack, M.S. Ferguson, O. Zilberberg, Physical Review Research 4 (2022). date_created: 2023-01-08T23:00:53Z date_published: 2022-12-01T00:00:00Z date_updated: 2023-02-13T09:08:28Z day: '01' ddc: - '530' department: - _id: MaSe doi: 10.1103/PhysRevResearch.4.043177 file: - access_level: open_access checksum: 556820cf6e4af77c8476e5b8f4114d1a content_type: application/pdf creator: dernst date_created: 2023-01-20T12:03:31Z date_updated: 2023-01-20T12:03:31Z file_id: '12328' file_name: 2022_PhysicalReviewResearch_Stocker.pdf file_size: 2941167 relation: main_file success: 1 file_date_updated: 2023-01-20T12:03:31Z has_accepted_license: '1' intvolume: ' 4' issue: '4' language: - iso: eng month: '12' oa: 1 oa_version: Published Version publication: Physical Review Research publication_identifier: issn: - 2643-1564 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Entanglement-based observables for quantum impurities tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 4 year: '2022' ... --- _id: '12276' abstract: - lang: eng text: Ongoing development of quantum simulators allows for a progressively finer degree of control of quantum many-body systems. This motivates the development of efficient approaches to facilitate the control of such systems and enable the preparation of nontrivial quantum states. Here we formulate an approach to control quantum systems based on matrix product states (MPSs). We compare counterdiabatic and leakage minimization approaches to the so-called local steering problem that consists in finding the best value of the control parameters for generating a unitary evolution of the specific MPS in a given direction. In order to benchmark the different approaches, we apply them to the generalization of the PXP model known to exhibit coherent quantum dynamics due to quantum many-body scars. We find that the leakage-based approach generally outperforms the counterdiabatic framework and use it to construct a Floquet model with quantum scars. We perform the first steps towards global trajectory optimization and demonstrate entanglement steering capabilities in the generalized PXP model. Finally, we apply our leakage minimization approach to construct quantum scars in the periodically driven nonintegrable Ising model. acknowledgement: We thank A. A. Michailidis for insightful discussions. M.L. and M.S. acknowledge support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 850899). D.A. is supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 864597) and by the Swiss National Science Foundation. The infinite TEBD simulations were performed using the ITensor library [67]. article_number: '030343' article_processing_charge: No article_type: original author: - first_name: Marko full_name: Ljubotina, Marko id: F75EE9BE-5C90-11EA-905D-16643DDC885E last_name: Ljubotina - first_name: Barbara full_name: Roos, Barbara id: 5DA90512-D80F-11E9-8994-2E2EE6697425 last_name: Roos orcid: 0000-0002-9071-5880 - first_name: Dmitry A. full_name: Abanin, Dmitry A. last_name: Abanin - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Ljubotina M, Roos B, Abanin DA, Serbyn M. Optimal steering of matrix product states and quantum many-body scars. PRX Quantum. 2022;3(3). doi:10.1103/prxquantum.3.030343 apa: Ljubotina, M., Roos, B., Abanin, D. A., & Serbyn, M. (2022). Optimal steering of matrix product states and quantum many-body scars. PRX Quantum. American Physical Society. https://doi.org/10.1103/prxquantum.3.030343 chicago: Ljubotina, Marko, Barbara Roos, Dmitry A. Abanin, and Maksym Serbyn. “Optimal Steering of Matrix Product States and Quantum Many-Body Scars.” PRX Quantum. American Physical Society, 2022. https://doi.org/10.1103/prxquantum.3.030343. ieee: M. Ljubotina, B. Roos, D. A. Abanin, and M. Serbyn, “Optimal steering of matrix product states and quantum many-body scars,” PRX Quantum, vol. 3, no. 3. American Physical Society, 2022. ista: Ljubotina M, Roos B, Abanin DA, Serbyn M. 2022. Optimal steering of matrix product states and quantum many-body scars. PRX Quantum. 3(3), 030343. mla: Ljubotina, Marko, et al. “Optimal Steering of Matrix Product States and Quantum Many-Body Scars.” PRX Quantum, vol. 3, no. 3, 030343, American Physical Society, 2022, doi:10.1103/prxquantum.3.030343. short: M. Ljubotina, B. Roos, D.A. Abanin, M. Serbyn, PRX Quantum 3 (2022). date_created: 2023-01-16T10:01:56Z date_published: 2022-09-23T00:00:00Z date_updated: 2023-01-30T11:05:23Z day: '23' ddc: - '530' department: - _id: MaSe - _id: RoSe doi: 10.1103/prxquantum.3.030343 ec_funded: 1 external_id: arxiv: - '2204.02899' file: - access_level: open_access checksum: ef8f0a1b5a019b3958009162de0fa4c3 content_type: application/pdf creator: dernst date_created: 2023-01-30T11:02:50Z date_updated: 2023-01-30T11:02:50Z file_id: '12457' file_name: 2022_PRXQuantum_Ljubotina.pdf file_size: 7661905 relation: main_file success: 1 file_date_updated: 2023-01-30T11:02:50Z has_accepted_license: '1' intvolume: ' 3' issue: '3' keyword: - General Medicine language: - iso: eng month: '09' oa: 1 oa_version: Published Version project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: PRX Quantum publication_identifier: eissn: - 2691-3399 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Optimal steering of matrix product states and quantum many-body scars tmp: 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) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 3 year: '2022' ... --- _id: '10863' abstract: - lang: eng text: 'Nonlinear optical responses are commonly used as a probe for studying the electronic properties of materials. For topological materials, studies thus far focused on photogalvanic electric currents, which are forbidden in centrosymmetric materials because they require broken inversion symmetry. In this Letter, we propose a class of symmetry-allowed responses for inversion-symmetric topological insulators with two doubly degenerate bands. We consider a specific example of such a response, the orbital current, and show that the sign of the response reflects the Z2 topological index, i.e., the orbital current changes sign at the transition between trivial and topological insulator phases. This is illustrated in two models of topological insulators: the Bernevig-Hughes-Zhang model and the 1T′ phase of transition metal dichalcogenides.' acknowledgement: "We are grateful to Takahiro Morimoto and Zhanybek Alpichshev for fruitful discussions. MD was supported by Austrian Agency for International Cooperation in Education and Research (OeAD-GmbH) and by the John Seo Fellowship at MIT. HI was supported by JSPS KAKENHI Grant Numbers JP19K14649 and JP18H03676, and by UTokyo Global Activity Support Program for\r\nYoung Researchers." article_number: L121407 article_processing_charge: No article_type: letter_note author: - first_name: Margarita full_name: Davydova, Margarita last_name: Davydova - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 - first_name: Hiroaki full_name: Ishizuka, Hiroaki last_name: Ishizuka citation: ama: Davydova M, Serbyn M, Ishizuka H. Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials. Physical Review B. 2022;105. doi:10.1103/PhysRevB.105.L121407 apa: Davydova, M., Serbyn, M., & Ishizuka, H. (2022). Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials. Physical Review B. American Physical Society. https://doi.org/10.1103/PhysRevB.105.L121407 chicago: Davydova, Margarita, Maksym Serbyn, and Hiroaki Ishizuka. “Symmetry-Allowed Nonlinear Orbital Response across the Topological Phase Transition in Centrosymmetric Materials.” Physical Review B. American Physical Society, 2022. https://doi.org/10.1103/PhysRevB.105.L121407. ieee: M. Davydova, M. Serbyn, and H. Ishizuka, “Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials,” Physical Review B, vol. 105. American Physical Society, 2022. ista: Davydova M, Serbyn M, Ishizuka H. 2022. Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials. Physical Review B. 105, L121407. mla: Davydova, Margarita, et al. “Symmetry-Allowed Nonlinear Orbital Response across the Topological Phase Transition in Centrosymmetric Materials.” Physical Review B, vol. 105, L121407, American Physical Society, 2022, doi:10.1103/PhysRevB.105.L121407. short: M. Davydova, M. Serbyn, H. Ishizuka, Physical Review B 105 (2022). date_created: 2022-03-18T10:20:46Z date_published: 2022-03-17T00:00:00Z date_updated: 2023-08-03T06:09:56Z day: '17' department: - _id: MaSe doi: 10.1103/PhysRevB.105.L121407 external_id: arxiv: - '2101.08277' isi: - '000800752500001' intvolume: ' 105' isi: 1 language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2101.08277 month: '03' oa: 1 oa_version: Preprint publication: Physical Review B publication_identifier: issn: - 2469-9969 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 105 year: '2022' ... --- _id: '11337' abstract: - lang: eng text: 'Nonanalytic points in the return probability of a quantum state as a function of time, known as dynamical quantum phase transitions (DQPTs), have received great attention in recent years, but the understanding of their mechanism is still incomplete. In our recent work [Phys. Rev. Lett. 126, 040602 (2021)], we demonstrated that one-dimensional DQPTs can be produced by two distinct mechanisms, namely semiclassical precession and entanglement generation, leading to the definition of precession (pDQPTs) and entanglement (eDQPTs) dynamical quantum phase transitions. In this manuscript, we extend and investigate the notion of p- and eDQPTs in two-dimensional systems by considering semi-infinite ladders of varying width. For square lattices, we find that pDQPTs and eDQPTs persist and are characterized by similar phenomenology as in 1D: pDQPTs are associated with a magnetization sign change and a wide entanglement gap, while eDQPTs correspond to suppressed local observables and avoided crossings in the entanglement spectrum. However, DQPTs show higher sensitivity to the ladder width and other details, challenging the extrapolation to the thermodynamic limit especially for eDQPTs. Moving to honeycomb lattices, we also demonstrate that lattices with an odd number of nearest neighbors give rise to phenomenologies beyond the one-dimensional classification.' acknowledgement: "We acknowledge support by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 850899).\r\nS.D.N. also acknowledges funding from the Institute of Science and Technology (IST) Austria, and from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie Grant Agreement No. 754411." article_number: '165149' article_processing_charge: No article_type: original author: - first_name: Stefano full_name: De Nicola, Stefano id: 42832B76-F248-11E8-B48F-1D18A9856A87 last_name: De Nicola orcid: 0000-0002-4842-6671 - first_name: Alexios full_name: Michailidis, Alexios id: 36EBAD38-F248-11E8-B48F-1D18A9856A87 last_name: Michailidis - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: De Nicola S, Michailidis A, Serbyn M. Entanglement and precession in two-dimensional dynamical quantum phase transitions. Physical Review B. 2022;105. doi:10.1103/PhysRevB.105.165149 apa: De Nicola, S., Michailidis, A., & Serbyn, M. (2022). Entanglement and precession in two-dimensional dynamical quantum phase transitions. Physical Review B. American Physical Society. https://doi.org/10.1103/PhysRevB.105.165149 chicago: De Nicola, Stefano, Alexios Michailidis, and Maksym Serbyn. “Entanglement and Precession in Two-Dimensional Dynamical Quantum Phase Transitions.” Physical Review B. American Physical Society, 2022. https://doi.org/10.1103/PhysRevB.105.165149. ieee: S. De Nicola, A. Michailidis, and M. Serbyn, “Entanglement and precession in two-dimensional dynamical quantum phase transitions,” Physical Review B, vol. 105. American Physical Society, 2022. ista: De Nicola S, Michailidis A, Serbyn M. 2022. Entanglement and precession in two-dimensional dynamical quantum phase transitions. Physical Review B. 105, 165149. mla: De Nicola, Stefano, et al. “Entanglement and Precession in Two-Dimensional Dynamical Quantum Phase Transitions.” Physical Review B, vol. 105, 165149, American Physical Society, 2022, doi:10.1103/PhysRevB.105.165149. short: S. De Nicola, A. Michailidis, M. Serbyn, Physical Review B 105 (2022). date_created: 2022-04-28T08:06:10Z date_published: 2022-04-15T00:00:00Z date_updated: 2023-08-03T06:33:33Z day: '15' department: - _id: MaSe doi: 10.1103/PhysRevB.105.165149 ec_funded: 1 external_id: arxiv: - '2112.11273' isi: - '000806812400004' intvolume: ' 105' isi: 1 language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2112.11273' month: '04' oa: 1 oa_version: Preprint project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' - _id: 260C2330-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '754411' name: ISTplus - Postdoctoral Fellowships publication: Physical Review B publication_identifier: eisbn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' status: public title: Entanglement and precession in two-dimensional dynamical quantum phase transitions type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 105 year: '2022' ... --- _id: '11379' abstract: - lang: eng text: Bernal-stacked multilayer graphene is a versatile platform to explore quantum transport phenomena and interaction physics due to its exceptional tunability via electrostatic gating. For instance, upon applying a perpendicular electric field, its band structure exhibits several off-center Dirac points (so-called Dirac gullies) in each valley. Here, the formation of Dirac gullies and the interaction-induced breakdown of gully coherence is explored via magnetotransport measurements in high-quality Bernal-stacked (ABA) trilayer graphene. At zero magnetic field, multiple Lifshitz transitions indicating the formation of Dirac gullies are identified. In the quantum Hall regime, the emergence of Dirac gullies is evident as an increase in Landau level degeneracy. When tuning both electric and magnetic fields, electron–electron interactions can be controllably enhanced until, beyond critical electric and magnetic fields, the gully degeneracy is eventually lifted. The arising correlated ground state is consistent with a previously predicted nematic phase that spontaneously breaks the rotational gully symmetry. acknowledgement: "We acknowledge funding from the Center for Nanoscience (CeNS) and by the Deutsche\r\nForschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy-EXC-2111-390814868 (MCQST). K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan (Grant Number PMXP0112101001) and JSPS KAKENHI (Grant Numbers 19H05790 and JP20H00354)." article_processing_charge: No article_type: original author: - first_name: Felix full_name: Winterer, Felix last_name: Winterer - first_name: Anna M. full_name: Seiler, Anna M. last_name: Seiler - first_name: Areg full_name: Ghazaryan, Areg id: 4AF46FD6-F248-11E8-B48F-1D18A9856A87 last_name: Ghazaryan orcid: 0000-0001-9666-3543 - first_name: Fabian R. full_name: Geisenhof, Fabian R. last_name: Geisenhof - first_name: Kenji full_name: Watanabe, Kenji last_name: Watanabe - first_name: Takashi full_name: Taniguchi, Takashi last_name: Taniguchi - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 - first_name: R. Thomas full_name: Weitz, R. Thomas last_name: Weitz citation: ama: Winterer F, Seiler AM, Ghazaryan A, et al. Spontaneous gully-polarized quantum hall states in ABA trilayer graphene. Nano Letters. 2022;22(8):3317-3322. doi:10.1021/acs.nanolett.2c00435 apa: Winterer, F., Seiler, A. M., Ghazaryan, A., Geisenhof, F. R., Watanabe, K., Taniguchi, T., … Weitz, R. T. (2022). Spontaneous gully-polarized quantum hall states in ABA trilayer graphene. Nano Letters. American Chemical Society. https://doi.org/10.1021/acs.nanolett.2c00435 chicago: Winterer, Felix, Anna M. Seiler, Areg Ghazaryan, Fabian R. Geisenhof, Kenji Watanabe, Takashi Taniguchi, Maksym Serbyn, and R. Thomas Weitz. “Spontaneous Gully-Polarized Quantum Hall States in ABA Trilayer Graphene.” Nano Letters. American Chemical Society, 2022. https://doi.org/10.1021/acs.nanolett.2c00435. ieee: F. Winterer et al., “Spontaneous gully-polarized quantum hall states in ABA trilayer graphene,” Nano Letters, vol. 22, no. 8. American Chemical Society, pp. 3317–3322, 2022. ista: Winterer F, Seiler AM, Ghazaryan A, Geisenhof FR, Watanabe K, Taniguchi T, Serbyn M, Weitz RT. 2022. Spontaneous gully-polarized quantum hall states in ABA trilayer graphene. Nano Letters. 22(8), 3317–3322. mla: Winterer, Felix, et al. “Spontaneous Gully-Polarized Quantum Hall States in ABA Trilayer Graphene.” Nano Letters, vol. 22, no. 8, American Chemical Society, 2022, pp. 3317–22, doi:10.1021/acs.nanolett.2c00435. short: F. Winterer, A.M. Seiler, A. Ghazaryan, F.R. Geisenhof, K. Watanabe, T. Taniguchi, M. Serbyn, R.T. Weitz, Nano Letters 22 (2022) 3317–3322. date_created: 2022-05-15T22:01:41Z date_published: 2022-04-27T00:00:00Z date_updated: 2023-08-03T07:12:45Z day: '27' department: - _id: MaSe doi: 10.1021/acs.nanolett.2c00435 external_id: arxiv: - '2109.00556' isi: - '000809056900019' intvolume: ' 22' isi: 1 issue: '8' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2109.00556' month: '04' oa: 1 oa_version: Preprint page: 3317-3322 publication: Nano Letters publication_identifier: eissn: - '15306992' issn: - '15306984' publication_status: published publisher: American Chemical Society quality_controlled: '1' scopus_import: '1' status: public title: Spontaneous gully-polarized quantum hall states in ABA trilayer graphene type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 22 year: '2022' ... --- _id: '11470' abstract: - lang: eng 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. acknowledged_ssus: - _id: ScienComp 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. article_number: L220203 article_processing_charge: No article_type: original author: - first_name: Pietro full_name: Brighi, Pietro id: 4115AF5C-F248-11E8-B48F-1D18A9856A87 last_name: Brighi orcid: 0000-0002-7969-2729 - first_name: Alexios A. full_name: Michailidis, Alexios A. last_name: Michailidis - first_name: Dmitry A. full_name: Abanin, Dmitry A. last_name: Abanin - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Brighi P, Michailidis AA, Abanin DA, Serbyn M. Propagation of many-body localization in an Anderson insulator. Physical Review B. 2022;105(22). doi:10.1103/physrevb.105.l220203 apa: Brighi, P., Michailidis, A. A., Abanin, D. A., & Serbyn, M. (2022). Propagation of many-body localization in an Anderson insulator. Physical Review B. American Physical Society. https://doi.org/10.1103/physrevb.105.l220203 chicago: Brighi, Pietro, Alexios A. Michailidis, Dmitry A. Abanin, and Maksym Serbyn. “Propagation of Many-Body Localization in an Anderson Insulator.” Physical Review B. American Physical Society, 2022. https://doi.org/10.1103/physrevb.105.l220203. ieee: P. Brighi, A. A. Michailidis, D. A. Abanin, and M. Serbyn, “Propagation of many-body localization in an Anderson insulator,” Physical Review B, vol. 105, no. 22. American Physical Society, 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. mla: Brighi, Pietro, et al. “Propagation of Many-Body Localization in an Anderson Insulator.” Physical Review B, vol. 105, no. 22, L220203, American Physical Society, 2022, doi:10.1103/physrevb.105.l220203. short: P. Brighi, A.A. Michailidis, D.A. Abanin, M. Serbyn, Physical Review B 105 (2022). date_created: 2022-06-29T20:20:47Z date_published: 2022-06-27T00:00:00Z date_updated: 2023-08-03T07:23:52Z day: '27' department: - _id: MaSe doi: 10.1103/physrevb.105.l220203 ec_funded: 1 external_id: arxiv: - '2109.07332' isi: - '000823050000012' intvolume: ' 105' isi: 1 issue: '22' language: - iso: eng main_file_link: - open_access: '1' url: ' https://doi.org/10.48550/arXiv.2109.07332' month: '06' oa: 1 oa_version: Preprint project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' related_material: record: - id: '12732' relation: dissertation_contains status: public status: public title: Propagation of many-body localization in an Anderson insulator type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 105 year: '2022' ...