Article
Physics, Multidisciplinary
Ahana Chakraborty, Rajdeep Sensarma
Summary: This study introduces a new field theoretic method for calculating Renyi entropy of interacting bosons in subsystems without using replica methods. The method can be applied to dynamics of open and closed quantum systems, and can determine the relationship between the initial state and final density matrix to predict the behavior of entropy over time. The approach also shows that the entropy in non-Markovian dynamics approaches a steady-state value with exponents determined by nonanalyticities of the system's environment.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Marcin Plodzien, Maciej Lewenstein, Emilia Witkowska, Jan Chwedenczuk
Summary: We demonstrate that one-axis twisting (OAT) is a powerful source of many-body Bell correlations for creating nonclassical states of bosonic qubits. We develop an analytical and universal treatment that allows us to identify the critical time for the emergence of Bell correlations and predict their depth at subsequent times. Our findings are illustrated using a highly nontrivial example of OAT dynamics generated with the Bose-Hubbard model.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Yong-Yi Wang, Zheng-Hang Sun, Heng Fan
Summary: Recent research has shown a disorder-free many-body localization (MBL), known as Stark MBL, in an interacting system with a linear potential. The study investigates Stark MBL in two types of superconducting circuits and calculates entanglement entropy and participate entropy of highly excited eigenstates. The findings suggest that superconducting circuits are a promising platform for studying the critical properties of the Stark MBL transition.
Article
Materials Science, Multidisciplinary
Bin-Bin Chen, Hong-Hao Tu, Zi Yang Meng, Meng Cheng
Summary: We introduce a new many-body topological invariant, called the topological disorder parameter (TDP), to characterize gapped quantum phases with global internal symmetry in 2 + 1 dimensions. Inspired by a topological quantum field theory interpretation, we establish a formula relating the TDP to the quantum dimension of the symmetry defect. We validate the effectiveness and applicability of the TDP through analytical and numerical investigations of several lattice models of topological phases.
Review
Physics, Multidisciplinary
Irenee Frerot, Matteo Fadel, Maciej Lewenstein
Summary: This review discusses methods for detecting and characterizing quantum correlations in many-body systems, with a focus on scalable approaches. It introduces concepts such as quantum entanglement, Einstein-Podolsky-Rosen steering, and Bell nonlocality, both in the bipartite scenario and their generalizations to multipartite cases. The review also covers recent progress in characterizing quantum correlations, experimental techniques for preparing and measuring highly-entangled many-body systems, and the challenges associated with each platform. It concludes with a list of open problems in the field.
REPORTS ON PROGRESS IN PHYSICS
(2023)
Article
Quantum Science & Technology
Poetri Sonya Tarabunga, Emanuele Tirrito, Titas Chanda, Marcello Dalmonte
Summary: We introduce a method to measure many-body magic in quantum systems based on a statistical exploration of Pauli strings via Markov chains. The method allows efficient extraction of magic contained in correlations between widely separated subsystems. The importance of magic in many-body systems is demonstrated through various discoveries, such as its association with conformal quantum criticality and its ability to identify phase transitions.
Article
Materials Science, Multidisciplinary
Ferdinand Evers, Ishita Modak, Soumya Bera
Summary: After a decade of debate, it is now widely agreed that generic disordered quantum wires do not exhibit many-body localization within a reasonable range of disorder values. This study sheds new light on delocalization physics and suggests that while there is no universal time scale, the concept of an internal clock still holds in an ensemble sense. By analyzing imbalance and entropy, the researchers found that average entropy appropriately models the ensemble-averaged internal clock.
Article
Physics, Condensed Matter
Longhui Shen, Jia Bao, Bin Guo, Zhaoyu Sun
Summary: We investigate the many-body localization (MBL) transitions in a spin-1/2 Heisenberg chain with an on-site random magnetic field by employing global quantum discord (GQD). The MBL critical point is estimated to be around W-c = 3.8 using disorder-averaged GQD and finite-size scaling analysis. We compare the results of GQD with those of half-chain entanglement entropy (EE) and find that GQD is more robust in characterizing MBL.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Physics, Condensed Matter
Alexandre M. Souza, Roberto S. Sarthour, Ivan S. Oliveira
Summary: Entanglement has been an area of great interest since the early years of quantum mechanics. In recognition of their efforts in verifying the properties of entangled photons, the Nobel Prize in Physics for 2022 was awarded to Alain Aspect, John F. Clauser, and Anton Zeilinger, who are leading pioneers in this field. However, entanglement is not limited to photons and can occur among hundreds, millions, or even more particles in condensed matter systems. Quantum entanglement leads to strong non-classical correlations among particles, playing a crucial role in various properties of matter such as superconductivity and different forms of magnetic order that arise from highly correlated ground states in many-body systems.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Multidisciplinary Sciences
Joonhee Choi, Adam L. L. Shaw, Ivaylo S. S. Madjarov, Xin Xie, Ran Finkelstein, Jacob P. P. Covey, Jordan S. S. Cotler, Daniel K. K. Mark, Hsin-Yuan Huang, Anant Kale, Hannes Pichler, Fernando G. S. L. Brandao, Soonwon Choi, Manuel Endres
Summary: Producing random quantum states is increasingly important in modern quantum science, with applications in both theory and practice. Randomly distributed, pure quantum state ensembles play a key role in understanding complexity in quantum circuits and black holes, as well as benchmarking quantum devices in tests of quantum advantage. This study solves the problem of creating random ensembles by predicting and observing their emergence naturally under time-independent Hamiltonian dynamics, and develops an efficient benchmarking protocol and fidelity estimation scheme with broad applicability.
Article
Physics, Multidisciplinary
Irenee Frerot, Tommaso Roscilde
Summary: Bell nonlocality is the ultimate consequence of quantum entanglement, challenging classical beliefs. Investigating Bell nonlocality in many-body systems is a formidable challenge, but an efficient variational scheme has been proposed and validated.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Julian Leonard, Sooshin Kim, Matthew Rispoli, Alexander Lukin, Robert Schittko, Joyce Kwan, Eugene Demler, Dries Sels, Markus Greiner
Summary: Strongly correlated systems can exhibit unexpected phenomena when brought far from equilibrium, such as many-body localization preventing systems from reaching thermal equilibrium even at long times. The presence of small thermal inclusions can hinder the stability of the many-body localized phase, leading to the delocalization of the entire system through an avalanche propagation mechanism. This study explores the dynamics of a variable-sized thermal inclusion coupled to a many-body localized system and provides evidence for accelerated transport of the thermal inclusion into the localized region, as well as monitoring the spreading avalanche and thermalization process within the system.
Article
Materials Science, Multidisciplinary
Alexander Nico-Katz, Abolfazl Bayat, Sougato Bose
Summary: A key feature of many-body localization is the breaking of ergodicity and the emergence of local memory. Existing studies have partially captured the dynamics of local memory, but suffer from various limitations. This study introduces the dynamical Holevo quantity to address these limitations and provides a comprehensive analysis.
Article
Mechanics
Taiki Haga, Shin-ich Sasa
Summary: This study investigates the emergence of classical chaos from the microscopic description of quantum mechanics. By designing a quantum lattice system and taking an appropriate continuum limit, known as the 'Hamiltonian equation limit', the researchers simulate classical chaos in a quantum framework. A key concept in their analysis is the measurement of entanglement entropy between microscopic degrees of freedom within each block and the macroscopic degrees of freedom that define the large-scale structure of the wave function. Numerical simulations show that chaos only emerges in the Hamiltonian equation limit when the long-time average of the interscale entanglement entropy (IEE) becomes positive, and the initial growth rate of entropy is proportional to that of the coarse-grained Gibbs entropy in the corresponding classical system.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2022)
Article
Physics, Multidisciplinary
Jef Pauwels, Armin Tavakoli, Erik Woodhead, Stefano Pironio
Summary: This article explores correlations in scenarios involving both entanglement and communication, focusing on entanglement-assisted prepare-and-measure scenarios. By establishing elementary relations between standard classical and quantum communication and their entanglement-assisted counterparts, it is found that higher-dimensional entanglement further enhances the power of bits or qubits. Additionally, a characterization of generalized dense coding protocols is provided, and evidence is presented that resources with a small information capacity, such as bare qutrits, can sometimes produce stronger correlations. The article concludes with several conjectures and a list of interesting open problems.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
A. Bohrdt, Y. Wang, J. Koepsell, M. Kanasz-Nagy, E. Demler, F. Grusdt
Summary: The study reveals strong non-Gaussian correlations in doped quantum antiferromagnets and shows that higher-order correlations dominate over lower-order terms. By analyzing fifth-order spin-charge correlations in the t - J model, the research sheds light on the mobility of dopants and contrasts the results to predictions using models based on doped quantum spin liquids. These predictions can be tested in quantum simulators of the 2D Fermi-Hubbard model, offering insight into the microscopic nature of charge carriers in the Hubbard model relevant to high-T-c superconductivity.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Yuto Ashida, Atac Imamoglu, Eugene Demler
Summary: This study proposes a nonperturbative approach to analyze correlations in quantum light-matter systems at strong coupling, achieving decoupling of light and matter degrees of freedom through a unitary transformation. It demonstrates the versatility of the method by applying it to specific models and discusses a generalization to spatially varying electromagnetic modes.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Kai Klocke, David Aasen, Roger S. K. Mong, Eugene A. Demler, Jason Alicea
Summary: This research introduces a time-domain probing method for the edge and quasiparticle content of non-Abelian spin liquids, utilizing ancillary quantum spins to reveal edge-state velocity and detect individual non-Abelian anyons and emergent fermions in suitable geometries. Anticipated applications include various topological phases in solid-state and cold-atoms settings.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Michele Buzzi, Gregor Jotzu, Andrea Cavalleri, J. Ignacio Cirac, Eugene A. Demler, Bertrand Halperin, Mikhail D. Lukin, Tao Shi, Yao Wang, Daniel Podolsky
Summary: The study introduces a novel nonequilibrium phenomenon where a prompt quench from a metal to a transient superconducting state induces large oscillations of the order parameter amplitude. The oscillating mode is suggested to act as a source of parametric amplification of the incident radiation, with experimental results on optically driven K3C60 supporting these predictions. The effect diminishes when the excitation onset surpasses the Higgs-mode period, presenting new possibilities for inducing nonlinear optical effects using collective modes in many-body systems.
Article
Physics, Multidisciplinary
Geoffrey Ji, Muqing Xu, Lev Haldar Kendrick, Christie S. Chiu, Justus C. Brueggenjuergen, Daniel Greif, Annabelle Bohrdt, Fabian Grusdt, Eugene Demler, Martin Lebrat, Markus Greiner
Summary: Understanding the interplay between charge and spin in quantum many-body systems, particularly in the Fermi-Hubbard model, is crucial for explaining emergent properties like high-temperature superconductivity. This study used a cold-atom quantum simulator to observe the formation and spreading dynamics of magnetic polarons, revealing the strong coupling between density and spin in their formation process. It provides insights into out-of-equilibrium emergent phenomena in the Fermi-Hubbard model.
Article
Physics, Multidisciplinary
A. Bohrdt, E. Demler, F. Grusdt
Summary: This study introduces a rotational variant of ARPES spectroscopy and identifies long-lived rotational resonances for individual dopants, which are interpreted as direct indicators of the microscopic structure of spinon-chargon bound states. By establishing a linear dependence of rotational energy on superexchange coupling, researchers explore emergent universal features of strongly correlated electron systems.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Alfred Zong, Pavel E. Dolgirev, Anshul Kogar, Yifan Su, Xiaozhe Shen, Joshua A. W. Straquadine, Xirui Wang, Duan Luo, Michael E. Kozina, Alexander H. Reid, Renkai Li, Jie Yang, Stephen P. Weathersby, Suji Park, Edbert J. Sie, Pablo Jarillo-Herrero, Ian R. Fisher, Xijie Wang, Eugene Demler, Nuh Gedik
Summary: Engineering novel states of matter with light is a cutting-edge area of materials research, with a focus on realizing broken-symmetry phases through ultrashort laser pulses. Experimental findings suggest that light-induced CDW consists solely of order parameter fluctuations, similar to critical fluctuations in equilibrium. These results indicate that materials with strong equilibrium fluctuations may host hidden orders after laser excitation.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Joannis Koepsell, Dominik Bourgund, Pimonpan Sompet, Sarah Hirthe, Annabelle Bohrdt, Yao Wang, Fabian Grusdt, Eugene Demler, Guillaume Salomon, Christian Gross, Immanuel Bloch
Summary: The research reveals the competition between antiferromagnetism and hole motion in two-dimensional Mott insulators, as well as the transition from an anomalous metal to a conventional Fermi liquid with varying doping levels. Using a cold-atom quantum simulator, the transformation of multipoint correlations between spins and holes is observed to change with increasing doping, with the crossover completed around 30% hole doping. This work provides insights into theoretical approaches and potential connections to lower-temperature phenomena.
Article
Physics, Multidisciplinary
Pavel E. Dolgirev, Yi-Fan Qu, Mikhail B. Zvonarev, Tao Shi, Eugene Demler
Summary: The Fermi-polaron problem involves the interaction between a mobile impurity and a fermionic medium, with conventional expectations suggesting dissipative dynamics, but research in a one-dimensional system has revealed a different type of polaron dynamics.
Article
Physics, Multidisciplinary
J. Knoerzer, T. Shi, E. Demler, J. Cirac
Summary: By studying trapped-ion quantum systems, we can gain insights into generalized Holstein models and benchmark expensive numerical calculations. Our focus is on simulating many-electron systems and examining the competition between charge-density wave order, fermion pairing, and phase separation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
A. von Hoegen, M. Fechner, M. Foerst, N. Taherian, E. Rowe, A. Ribak, J. Porras, B. Keimer, M. Michael, E. Demler, A. Cavalleri
Summary: In this study, it is shown that certain lattice vibrations in cuprate high-T-c superconductors can induce transient terahertz reflectivity features suggestive of nonequilibrium superconductivity above the critical temperature. Time-resolved measurements reveal a three-order-of-magnitude amplification of a 2.5-THz electronic mode in driven YBa2Cu3O6+x. Theoretical analysis explains these observations by proposing an amplification mechanism for finite-momentum Josephson plasma polaritons. The study also emphasizes the significance of nonlinear mode mixing in amplifying fluctuating modes above the transition temperature in a wide range of materials.
Article
Physics, Multidisciplinary
Yao Wang, Annabelle Bohrdt, Shuhan Ding, Joannis Koepsell, Eugene Demler, Fabian Grusdt
Summary: This paper explores the extension of using experimental measurements of higher-order correlation functions to study the equilibrium and dynamic properties of magnetic polarons in the 2D Hubbard model. The localization of dopants has a significant impact on its magnetic dressing, with different behaviors observed for mobile and immobile holes. The study also demonstrates the effects of thermal fluctuations on higher-order correlators and discusses the implications for understanding the interplay of spin and charge in doped Mott insulators.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Multidisciplinary Sciences
You Zhou, Jiho Sung, Elise Brutschea, Ilya Esterlis, Yao Wang, Giovanni Scuri, Ryan J. Gelly, Hoseok Heo, Takashi Taniguchi, Kenji Watanabe, Gergely Zarand, Mikhail D. Lukin, Philip Kim, Eugene Demler, Hongkun Park
Summary: Researchers observed the phenomenon of bilayer Wigner crystals in an atomically thin transition metal dichalcogenide heterostructure, consisting of two MoSe2 monolayers separated by hexagonal boron nitride, without the need for magnetic fields or moire potentials. Optical signatures revealed robust correlated insulating states at symmetric and asymmetric electron doping of the two MoSe2 layers at cryogenic temperatures. The Wigner crystal phases showed remarkable stability and underwent quantum and thermal melting transitions at high electron densities and temperatures. This study demonstrates that atomically thin heterostructures are a highly tunable platform for studying many-body electronic states and their liquid-solid and magnetic quantum phase transitions.
Article
Quantum Science & Technology
Ehud Altman, Kenneth R. Brown, Giuseppe Carleo, Lincoln D. Carr, Eugene Demler, Cheng Chin, Brian DeMarco, Sophia E. Economou, Mark A. Eriksson, Kai-Mei C. Fu, Markus Greiner, Kaden R. A. Hazzard, Randall G. Hulet, Alicia J. Kollar, Benjamin L. Lev, Mikhail D. Lukin, Ruichao Ma, Xiao Mi, Shashank Misra, Christopher Monroe, Kater Murch, Zaira Nazario, Kang-Kuen Ni, Andrew C. Potter, Pedram Roushan, Mark Saffman, Monika Schleier-Smith, Irfan Siddiqi, Raymond Simmonds, Meenakshi Singh, I. B. Spielman, Kristan Temme, David S. Weiss, Jelena Vuckovic, Vladan Vuletic, Jun Ye, Martin Zwierlein
Summary: Quantum simulators are a rapidly developing technology that utilizes entanglement and many-particle behavior to explore and solve scientific, engineering, and computational problems. With over 300 quantum simulators in operation worldwide, recent advances promise a golden age of quantum simulators that have the potential to address societal challenges and draw from various fields of study. Investment in a national quantum simulator program is seen as crucial to advancing this field and realizing practical applications of quantum machines.
Article
Materials Science, Multidisciplinary
Dries Sels, Eugene Demler
Summary: Quantum phase estimation is utilized to compute the dynamical response functions of many-body quantum systems efficiently in polynomial time, by designing a circuit as a quantum generative model for high rank observables. The algorithm, requiring doubling the number of qubits compared to a simple analog simulator, can provide samples out of experimentally relevant spectra with logarithmic overhead.
