1
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Yao Y, Xiang L. Superconducting Quantum Simulation for Many-Body Physics beyond Equilibrium. ENTROPY (BASEL, SWITZERLAND) 2024; 26:592. [PMID: 39056954 PMCID: PMC11275873 DOI: 10.3390/e26070592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 07/07/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024]
Abstract
Quantum computing is an exciting field that uses quantum principles, such as quantum superposition and entanglement, to tackle complex computational problems. Superconducting quantum circuits, based on Josephson junctions, is one of the most promising physical realizations to achieve the long-term goal of building fault-tolerant quantum computers. The past decade has witnessed the rapid development of this field, where many intermediate-scale multi-qubit experiments emerged to simulate nonequilibrium quantum many-body dynamics that are challenging for classical computers. Here, we review the basic concepts of superconducting quantum simulation and their recent experimental progress in exploring exotic nonequilibrium quantum phenomena emerging in strongly interacting many-body systems, e.g., many-body localization, quantum many-body scars, and discrete time crystals. We further discuss the prospects of quantum simulation experiments to truly solve open problems in nonequilibrium many-body systems.
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Affiliation(s)
- Yunyan Yao
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Department of Physics, Zhejiang University, Hangzhou 311200, China
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2
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Atanasova H, Erpenbeck A, Gull E, Lev YB, Cohen G. Stark Many-Body Localization in Interacting Infinite Dimensional Systems. PHYSICAL REVIEW LETTERS 2024; 132:166301. [PMID: 38701447 DOI: 10.1103/physrevlett.132.166301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/22/2024] [Accepted: 03/29/2024] [Indexed: 05/05/2024]
Abstract
We study bulk particle transport in a Fermi-Hubbard model on an infinite-dimensional Bethe lattice, driven by a constant electric field. Previous numerical studies showed that one dimensional analogs of this system exhibit a breakdown of diffusion due to Stark many-body localization at least up to time that scales exponentially with the system size. Here, we consider systems initially in a spin density wave state using a combination of numerically exact and approximate techniques. We show that for sufficiently weak electric fields, the wave's momentum component decays exponentially with time in a way consistent with normal diffusion. By studying different wavelengths, we extract the dynamical exponent and the generalized diffusion coefficient at each field strength. Interestingly, we find a nonmonotonic dependence of the dynamical exponent on the electric field. As the field increases toward a critical value proportional to the Hubbard interaction strength, transport slows down, becoming subdiffusive. At large interaction strengths, however, transport speeds up again with increasing field, exhibiting superdiffusive characteristics when the electric field is comparable to the interaction strength. Eventually, at the large field limit, localization occurs and the current through the system is suppressed.
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Affiliation(s)
| | - André Erpenbeck
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Emanuel Gull
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Yevgeny Bar Lev
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Guy Cohen
- School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
- The Raymond and Beverley Sackler Center for Computational Molecular and Materials Science, Tel Aviv University, Tel Aviv 6997801, Israel
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3
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Feng L, Katz O, Haack C, Maghrebi M, Gorshkov AV, Gong Z, Cetina M, Monroe C. Continuous symmetry breaking in a trapped-ion spin chain. Nature 2023; 623:713-717. [PMID: 37968402 DOI: 10.1038/s41586-023-06656-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 09/20/2023] [Indexed: 11/17/2023]
Abstract
One-dimensional systems exhibiting a continuous symmetry can host quantum phases of matter with true long-range order only in the presence of sufficiently long-range interactions1. In most physical systems, however, the interactions are short-ranged, hindering the emergence of such phases in one dimension. Here we use a one-dimensional trapped-ion quantum simulator to prepare states with long-range spin order that extends over the system size of up to 23 spins and is characteristic of the continuous symmetry-breaking phase of matter2,3. Our preparation relies on simultaneous control over an array of tightly focused individual addressing laser beams, generating long-range spin-spin interactions. We also observe a disordered phase with frustrated correlations. We further study the phases at different ranges of interaction and the out-of-equilibrium response to symmetry-breaking perturbations. This work opens an avenue to study new quantum phases and out-of-equilibrium dynamics in low-dimensional systems.
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Affiliation(s)
- Lei Feng
- Duke Quantum Center, Department of Physics and Electrical and Computer Engineering, Duke University, Durham, NC, USA.
| | - Or Katz
- Duke Quantum Center, Department of Physics and Electrical and Computer Engineering, Duke University, Durham, NC, USA.
| | - Casey Haack
- Department of Physics, Colorado School of Mines, Golden, CO, USA
| | - Mohammad Maghrebi
- Department of Physics and Astronomy, Michigan State University, East Lansings, MI, USA
| | - Alexey V Gorshkov
- Joint Quantum Institute and Joint Center for Quantum Information and Computer Science, University of Maryland and NIST, College Park, MD, USA
| | - Zhexuan Gong
- Department of Physics, Colorado School of Mines, Golden, CO, USA
| | - Marko Cetina
- Duke Quantum Center, Department of Physics and Electrical and Computer Engineering, Duke University, Durham, NC, USA
| | - Christopher Monroe
- Duke Quantum Center, Department of Physics and Electrical and Computer Engineering, Duke University, Durham, NC, USA.
- IonQ, Inc., College Park, MD, USA.
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4
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He X, Yousefjani R, Bayat A. Stark Localization as a Resource for Weak-Field Sensing with Super-Heisenberg Precision. PHYSICAL REVIEW LETTERS 2023; 131:010801. [PMID: 37478450 DOI: 10.1103/physrevlett.131.010801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 06/05/2023] [Indexed: 07/23/2023]
Abstract
Gradient fields can effectively suppress particle tunneling in a lattice and localize the wave function at all energy scales, a phenomenon known as Stark localization. Here, we show that Stark systems can be used as a probe for the precise measurement of gradient fields, particularly in the weak-field regime where most sensors do not operate optimally. In the extended phase, Stark probes achieve super-Heisenberg precision, which is well beyond most of the known quantum sensing schemes. In the localized phase, the precision drops in a universal way showing fast convergence to the thermodynamic limit. For single-particle probes, we show that quantum-enhanced sensitivity, with super-Heisenberg precision, can be achieved through a simple position measurement for all the eigenstates across the entire spectrum. For such probes, we have identified several critical exponents of the Stark localization transition and established their relationship. Thermal fluctuations, whose universal behavior is identified, reduce the precision from super-Heisenberg to Heisenberg, still outperforming classical sensors. Multiparticle interacting probes also achieve super-Heisenberg scaling in their extended phase, which shows even further enhancement near the transition point. Quantum-enhanced sensitivity is still achievable even when state preparation time is included in resource analysis.
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Affiliation(s)
- Xingjian He
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610051, China
| | - Rozhin Yousefjani
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610051, China
| | - Abolfazl Bayat
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610051, China
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5
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Kloss B, Halimeh JC, Lazarides A, Bar Lev Y. Absence of localization in interacting spin chains with a discrete symmetry. Nat Commun 2023; 14:3778. [PMID: 37355694 DOI: 10.1038/s41467-023-39468-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 06/08/2023] [Indexed: 06/26/2023] Open
Abstract
Novel paradigms of strong ergodicity breaking have recently attracted significant attention in condensed matter physics. Understanding the exact conditions required for their emergence or breakdown not only sheds more light on thermalization and its absence in closed quantum many-body systems, but it also has potential benefits for applications in quantum information technology. A case of particular interest is many-body localization whose conditions are not yet fully settled. Here, we prove that spin chains symmetric under a combination of mirror and spin-flip symmetries and with a non-degenerate spectrum show finite spin transport at zero total magnetization and infinite temperature. We demonstrate this numerically using two prominent examples: the Stark many-body localization system (Stark-MBL) and the symmetrized many-body localization system (symmetrized-MBL). We provide evidence of delocalization at all energy densities and show that delocalization persists when the symmetry is broken. We use our results to construct two localized systems which, when coupled, delocalize each other. Our work demonstrates the dramatic effect symmetries can have on disordered systems, proves that the existence of exact resonances is not a sufficient condition for delocalization, and opens the door to generalization to higher spatial dimensions and different conservation laws.
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Affiliation(s)
- Benedikt Kloss
- Center for Computational Quantum Physics, Flatiron Institute, 162 Fifth Ave, New York, NY, 10010, USA.
| | - Jad C Halimeh
- Department of Physics and Arnold Sommerfeld Center for Theoretical Physics (ASC), Ludwig-Maximilians-Universität München, Theresienstraße 37, D-80333, München, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstraße 4, D-80799, München, Germany
| | - Achilleas Lazarides
- Interdisciplinary Centre for Mathematical Modelling and Department of Mathematical Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK
| | - Yevgeny Bar Lev
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel
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6
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Kohlert T, Scherg S, Sala P, Pollmann F, Hebbe Madhusudhana B, Bloch I, Aidelsburger M. Exploring the Regime of Fragmentation in Strongly Tilted Fermi-Hubbard Chains. PHYSICAL REVIEW LETTERS 2023; 130:010201. [PMID: 36669215 DOI: 10.1103/physrevlett.130.010201] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/09/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
Intriguingly, quantum many-body systems may defy thermalization even without disorder. One example is so-called fragmented models, where the many-body Hilbert space fragments into dynamically disconnected subspaces that are not determined by the global symmetries of the model. In this Letter we demonstrate that the tilted one-dimensional Fermi-Hubbard model naturally realizes distinct effective Hamiltonians that are expected to support nonergodic behavior due to fragmentation, even at resonances between the tilt energy and the Hubbard on site interaction. We find that the effective description captures the observed dynamics in experimentally accessible parameter ranges of moderate tilt values. Specifically, we observe a pronounced dependence of the relaxation dynamics on the initial doublon fraction, which directly reveals the microscopic processes of the fragmented model. Our results pave the way for future studies of nonergodic behavior in higher dimensions.
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Affiliation(s)
- Thomas Kohlert
- Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 Munich, Germany
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Sebastian Scherg
- Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 Munich, Germany
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Pablo Sala
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
- Department of Physics and Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany
| | - Frank Pollmann
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
- Department of Physics and Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany
| | - Bharath Hebbe Madhusudhana
- Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 Munich, Germany
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Immanuel Bloch
- Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 Munich, Germany
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Monika Aidelsburger
- Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 Munich, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
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7
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Down-conversion of a single photon as a probe of many-body localization. Nature 2023; 613:650-655. [PMID: 36697866 DOI: 10.1038/s41586-022-05615-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 12/01/2022] [Indexed: 01/26/2023]
Abstract
Decay of a particle into more particles is a ubiquitous phenomenon to interacting quantum systems, taking place in colliders, nuclear reactors or solids. In a nonlinear medium, even a single photon would decay by down-converting (splitting) into lower-frequency photons with the same total energy1, at a rate given by Fermi's golden rule. However, the energy-conservation condition cannot be matched precisely if the medium is finite and only supports quantized modes. In this case, the fate of the photon becomes the long-standing question of many-body localization, originally formulated as a gedanken experiment for the lifetime of a single Fermi-liquid quasiparticle confined to a quantum dot2. Here we implement such an experiment using a superconducting multimode cavity, the nonlinearity of which was tailored to strongly violate the photon-number conservation. The resulting interaction attempts to convert a single photon excitation into a shower of low-energy photons but fails owing to the many-body localization mechanism, which manifests as a striking spectral fine structure of multiparticle resonances at the standing-wave-mode frequencies of the cavity. Each resonance was identified as a many-body state of radiation composed of photons from a broad frequency range and not obeying Fermi's golden rule theory. Our result introduces a new platform to explore the fundamentals of many-body localization without having to control many atoms or qubits3-9.
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8
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Aeppli A, Chu A, Bothwell T, Kennedy CJ, Kedar D, He P, Rey AM, Ye J. Hamiltonian engineering of spin-orbit-coupled fermions in a Wannier-Stark optical lattice clock. SCIENCE ADVANCES 2022; 8:eadc9242. [PMID: 36223457 PMCID: PMC9555777 DOI: 10.1126/sciadv.adc9242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 08/25/2022] [Indexed: 06/16/2023]
Abstract
Engineering a Hamiltonian system with tunable interactions provides opportunities to optimize performance for quantum sensing and explore emerging phenomena of many-body systems. An optical lattice clock based on partially delocalized Wannier-Stark states in a gravity-tilted shallow lattice supports superior quantum coherence and adjustable interactions via spin-orbit coupling, thus presenting a powerful spin model realization. The relative strength of the on-site and off-site interactions can be tuned to achieve a zero density shift at a "magic" lattice depth. This mechanism, together with a large number of atoms, enables the demonstration of the most stable atomic clock while minimizing a key systematic uncertainty related to atomic density. Interactions can also be maximized by driving off-site Wannier-Stark transitions, realizing a ferromagnetic to paramagnetic dynamical phase transition.
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Affiliation(s)
- Alexander Aeppli
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
| | - Anjun Chu
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, CO 80309, USA
| | - Tobias Bothwell
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
| | - Colin J. Kennedy
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
| | - Dhruv Kedar
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
| | - Peiru He
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, CO 80309, USA
| | - Ana Maria Rey
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, CO 80309, USA
| | - Jun Ye
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
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9
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Li BW, Mei QX, Wu YK, Cai ML, Wang Y, Yao L, Zhou ZC, Duan LM. Observation of Non-Markovian Spin Dynamics in a Jaynes-Cummings-Hubbard Model Using a Trapped-Ion Quantum Simulator. PHYSICAL REVIEW LETTERS 2022; 129:140501. [PMID: 36240415 DOI: 10.1103/physrevlett.129.140501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
The Jaynes-Cummings-Hubbard (JCH) model is a fundamental many-body model for light-matter interaction. As a leading platform for quantum simulation, the trapped ion system has realized the JCH model for two to three ions. Here, we report the quantum simulation of the JCH model using up to 32 ions. We verify the simulation results even for large ion numbers by engineering low excitations and thus low effective dimensions; then we extend to 32 excitations for an effective dimension of 2^{77}, which is difficult for classical computers. By regarding the phonon modes as baths, we explore Markovian or non-Markovian spin dynamics in different parameter regimes of the JCH model, similar to quantum emitters in a structured photonic environment. We further examine the dependence of the non-Markovian dynamics on the effective Hilbert space dimension. Our Letter demonstrates the trapped ion system as a powerful quantum simulator for many-body physics and open quantum systems.
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Affiliation(s)
- B-W Li
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
| | - Q-X Mei
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
| | - Y-K Wu
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
| | - M-L Cai
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
- HYQ Co., Ltd., Beijing, 100176, People's Republic of China
| | - Y Wang
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
| | - L Yao
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
- HYQ Co., Ltd., Beijing, 100176, People's Republic of China
| | - Z-C Zhou
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
| | - L-M Duan
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, People's Republic of China
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10
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Balducci F, Gambassi A, Lerose A, Scardicchio A, Vanoni C. Localization and Melting of Interfaces in the Two-Dimensional Quantum Ising Model. PHYSICAL REVIEW LETTERS 2022; 129:120601. [PMID: 36179178 DOI: 10.1103/physrevlett.129.120601] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/10/2022] [Accepted: 08/04/2022] [Indexed: 06/16/2023]
Abstract
We study the nonequilibrium evolution of coexisting ferromagnetic domains in the two-dimensional quantum Ising model-a setup relevant in several contexts, from quantum nucleation dynamics and false-vacuum decay scenarios to recent experiments with Rydberg-atom arrays. We demonstrate that the quantum-fluctuating interface delimiting a large bubble can be studied as an effective one-dimensional system through a "holographic" mapping. For the considered model, the emergent interface excitations map to an integrable chain of fermionic particles. We discuss how this integrability is broken by geometric features of the bubbles and by corrections in inverse powers of the ferromagnetic coupling, and provide a lower bound to the timescale after which the bubble is ultimately expected to melt. Remarkably, we demonstrate that a symmetry-breaking longitudinal field gives rise to a robust ergodicity breaking in two dimensions, a phenomenon underpinned by Stark many-body localization of the emergent fermionic excitations of the interface.
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Affiliation(s)
- Federico Balducci
- SISSA-International School for Advanced Studies, via Bonomea 265, 34136 Trieste, Italy
- INFN Sezione di Trieste-Via Valerio 2, 34127 Trieste, Italy
- The Abdus Salam ICTP-Strada Costiera 11, 34151 Trieste, Italy
| | - Andrea Gambassi
- SISSA-International School for Advanced Studies, via Bonomea 265, 34136 Trieste, Italy
- INFN Sezione di Trieste-Via Valerio 2, 34127 Trieste, Italy
| | - Alessio Lerose
- Department of Theoretical Physics, University of Geneva-Quai Ernest-Ansermet 30, 1205 Geneva, Switzerland
| | - Antonello Scardicchio
- INFN Sezione di Trieste-Via Valerio 2, 34127 Trieste, Italy
- The Abdus Salam ICTP-Strada Costiera 11, 34151 Trieste, Italy
| | - Carlo Vanoni
- SISSA-International School for Advanced Studies, via Bonomea 265, 34136 Trieste, Italy
- INFN Sezione di Trieste-Via Valerio 2, 34127 Trieste, Italy
- The Abdus Salam ICTP-Strada Costiera 11, 34151 Trieste, Italy
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11
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Benavides-Riveros CL, Chen L, Schilling C, Mantilla S, Pittalis S. Excitations of Quantum Many-Body Systems via Purified Ensembles: A Unitary-Coupled-Cluster-Based Approach. PHYSICAL REVIEW LETTERS 2022; 129:066401. [PMID: 36018631 DOI: 10.1103/physrevlett.129.066401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
State-average calculations based on a mixture of states are increasingly being exploited across chemistry and physics as versatile procedures for addressing excitations of quantum many-body systems. If not too many states should need to be addressed, calculations performed on individual states are also a common option. Here we show how the two approaches can be merged into one method, dealing with a generalized yet single pure state. Implications in electronic structure calculations are discussed and for quantum computations are pointed out.
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Affiliation(s)
- Carlos L Benavides-Riveros
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany
- INO-CNR BEC Center, I-38123 Trento, Italy
| | - Lipeng Chen
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany
| | - Christian Schilling
- Faculty of Physics, Arnold Sommerfeld Centre for Theoretical Physics (ASC), Ludwig-Maximilians-Universität München, Theresienstrasse 37, 80333 München, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstrasse 4, 80799 München, Germany
| | - Sebastián Mantilla
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany
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12
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Li WH, Deng X, Santos L. Hilbert Space Shattering and Disorder-Free Localization in Polar Lattice Gases. PHYSICAL REVIEW LETTERS 2021; 127:260601. [PMID: 35029478 DOI: 10.1103/physrevlett.127.260601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 10/18/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
Emerging dynamical constraints resulting from intersite interactions severely limit particle mobility in polar lattice gases. Whereas in absence of disorder hard-core Hubbard models with only strong nearest-neighbor interactions present Hilbert space fragmentation but no many-body localization for typical states, the 1/r^{3} tail of the dipolar interaction results in Hilbert space shattering, as well as in a dramatically slowed down dynamics and eventual disorder-free localization. Our results show that the study of the intriguing interplay between disorder- and interaction-induced many-body localization is within reach of future experiments with magnetic atoms and polar molecules.
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Affiliation(s)
- Wei-Han Li
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany
| | - Xiaolong Deng
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany
| | - Luis Santos
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany
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13
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Guo Q, Cheng C, Li H, Xu S, Zhang P, Wang Z, Song C, Liu W, Ren W, Dong H, Mondaini R, Wang H. Stark Many-Body Localization on a Superconducting Quantum Processor. PHYSICAL REVIEW LETTERS 2021; 127:240502. [PMID: 34951777 DOI: 10.1103/physrevlett.127.240502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/08/2021] [Indexed: 06/14/2023]
Abstract
Quantum emulators, owing to their large degree of tunability and control, allow the observation of fine aspects of closed quantum many-body systems, as either the regime where thermalization takes place or when it is halted by the presence of disorder. The latter, dubbed many-body localization (MBL) phenomenon, describes the nonergodic behavior that is dynamically identified by the preservation of local information and slow entanglement growth. Here, we provide a precise observation of this same phenomenology in the case where the quenched on-site energy landscape is not disordered, but rather linearly varied, emulating the Stark MBL. To this end, we construct a quantum device composed of 29 functional superconducting qubits, faithfully reproducing the relaxation dynamics of a nonintegrable spin model. At large Stark potentials, local observables display periodic Bloch oscillations, a manifesting characteristic of the fragmentation of the Hilbert space in sectors that conserve dipole moments. The flexible programmability of our quantum emulator highlights its potential in helping the understanding of nontrivial quantum many-body problems, in direct complement to simulations in classical computers.
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Affiliation(s)
- Qiujiang Guo
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Chen Cheng
- School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China
- Beijing Computational Science Research Center, Beijing 100094, China
| | - Hekang Li
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Shibo Xu
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Pengfei Zhang
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Zhen Wang
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Chao Song
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Wuxin Liu
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Wenhui Ren
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Hang Dong
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
| | - Rubem Mondaini
- Beijing Computational Science Research Center, Beijing 100094, China
| | - H Wang
- Department of Physics and Hangzhou Innovation Center, Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Zhejiang University, Hangzhou 310027, China
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