Article
Materials Science, Multidisciplinary
Yongchan Yoo, Christopher David White, Brian Swingle
Summary: We use nonequilibrium steady states to study the effect of dissipation-assisted operator evolution (DAOE) on the scaling behavior of transport in one-dimensional spin chains. We consider three models in the XXZ family: the chaotic XXZ model with staggered anisotropy, the Bethe-ansatz integrable XXZ model with no external field and tunable interaction, and the Anderson localized disordered XY model which is free-fermion integrable. Our findings suggest that the effect of DAOE on transport is determined by its impact on the system's conserved quantities, with preservation of the symmetries leading to preserved scaling and breaking of the conserved quantities leading to diffusive scaling of transport.
Article
Physics, Multidisciplinary
Mohamad Niknam, Lea F. Santos, David G. Cory
Summary: The research proposes and experimentally measures an entropy that quantifies correlations among qubits in a nearly isolated quantum system. Due to spin-spin interactions, information flows from a central spin to surrounding ones forming clusters of multispin correlations that grow over time. A nuclear magnetic resonance experiment is used to directly measure the amplitudes of multispin correlations and compute the evolution of what is called correlation Renyi entropy, which continues to grow even after the equilibration of entanglement entropy. The study also analyzes how the saturation point and timescale for the equilibration of the correlation Renyi entropy depend on the system size.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Fluids & Plasmas
Thomas Veness, Kay Brandner
Summary: This article investigates the stability of steady states in many-body systems coupled to a large thermal reservoir. By modeling the system and the reservoir as classical spin chains and simulating the Hamiltonian dynamics, the authors find that at high frequencies, the system reaches a Floquet-type Gibbs state at the reservoir temperature, while at low frequencies, a global synchronized Gibbs state emerges with a potentially different temperature from the reservoir. The authors argue that although their analysis relies on specific properties of their setup, much of the phenomenology could be applicable to other systems.
Article
Optics
L. Fernandes, M. Wouters, J. Tempere
Summary: Spin-1 Bose gases quenched to spin degeneracy exhibit fragmentation, with a condensate appearing in multiple single-particle states. By considering dissipation, we improve the performance of the Gaussian variational ansatz and effectively suppress entanglement, capturing the formation of a fragmented condensate. We analyze the amount of dissipation required to maintain a nonfragmented state.
Article
Materials Science, Multidisciplinary
Guido Giachetti, Andrea Solfanelli, Lorenzo Correale, Nicole Defenu
Summary: An experimentally accessible order parameter is introduced to detect crystalline phases of discrete Floquet time crystals and serves as a diagnostic tool for chaos. The phase diagram of the long-range kicked Ising model is investigated, revealing self-similar fractal boundaries.
Article
Physics, Multidisciplinary
Yoshihiro Nakato
Summary: This paper proposes a reasonable explanation for the increase of entropy in an isolated system by taking into account the spontaneous spreading of microscopic particles, such as electrons and atomic nuclei, into every possible spatial position. By using the Hamiltonian operator and wave function, a plausible definition for the entropy of an isolated system is provided, establishing a solid foundation for thermodynamics. Additionally, the new theory offers a new physical meaning of entropy for further studies on irreversible processes in nature.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2021)
Article
Materials Science, Multidisciplinary
Christopher M. Langlett, Zhi-Cheng Yang, Julia Wildeboer, Alexey Gorshkov, Thomas Iadecola, Shenglong Xu
Summary: This study develops a generic construction that embeds a new class of quantum many-body scars, called rainbow scars, into the spectrum of an arbitrary Hamiltonian. Unlike other examples of quantum many-body scars, rainbow scars display extensive bipartite entanglement entropy and can occur multiple times or even throughout the spectrum in the presence of internal symmetries.
Article
Materials Science, Multidisciplinary
Gianluca Francica, Luca Dell'Anna
Summary: In this study, we investigate the effects of the interaction range on the Hilbert-space fragmentation and many-body scar states. We find that scar states and weak fragmentation can survive for almost any range of the coupling. Additionally, when the interaction range is small enough, there are sectors with definite symmetries that display an algebraic decay in the ratio between the dimension of their largest fragment and their dimension.
Article
Materials Science, Multidisciplinary
Janez Bonca, Marcin Mierzejewski
Summary: We discuss the interplay between many-body localization and spin symmetry by studying the time evolution of several observables in the anisotropic t-J model. The results show that odd operators relax towards equilibrium values at short timescales in the case of symmetry-preserving disorder, while even operators and level statistics exhibit localization within each symmetry sector.
Article
Materials Science, Multidisciplinary
Michele Coppola, Emanuele Tirrito, Dragi Karevski, Mario Collura
Summary: The nonequilibrium dynamics of quantum systems under measurement protocols has attracted attention due to its impact on the scaling law of bipartite entanglement entropy. However, it is still unclear how these different nonequilibrium regimes appear and whether they persist in the thermodynamic limit. In this study, a one-dimensional quadratic fermionic model is used to investigate these questions, revealing a qualitative modification of the time growth of the entanglement entropy induced by local projective measurements. Nevertheless, in the thermodynamic limit, the logarithmic behavior of the entanglement entropy in the stationary regime does not survive, and a single area-law phase is identified for any finite value of the measurement rate.
Article
Physics, Multidisciplinary
Che-Hsiu Hsueh, Chi-Ho Cheng, Tzyy-Leng Horng, Wen-Chin Wu
Summary: This study investigates the H-theorem in an isolated quantum harmonic oscillator through the time-dependent Schrodinger equation. The effect of potential in producing entropy is examined in detail, revealing that the introduction of a barrier potential in a harmonic trap leads to the thermalization of the system. It is also observed that a coherent mechanical energy transforms into incoherent thermal energy during thermalization, accompanied by the decoherence of the oscillating wave packet.
Article
Materials Science, Multidisciplinary
Stefano Marcantoni, Federico Carollo, Filippo M. Gambetta, Igor Lesanovsky, Ulrich Schneider, Juan P. Garrahan
Summary: We study the effect of spatially correlated classical noise on both Anderson and many-body localization of a disordered fermionic chain. We find prominent signatures of localization even in the presence of time-dependent noise. For sufficiently strong static disorder, we observe the onset of metastability, which becomes more prominent with stronger spatial correlations of the noise. We identify a simple scaling behavior of the relevant relaxation times in terms of the static disorder and noise correlation length.
Article
Physics, Multidisciplinary
Somsubhra Ghosh, Indranil Paul, K. Sengupta
Summary: We study a fermionic chain with driven nearest-neighbor interaction and find that it exhibits prethermal strong Hilbert space fragmentation (HSF) at specific drive frequencies omega(*)(m) and high drive amplitudes. This is the first realization of strong HSF for out-of-equilibrium systems. We derive analytic expressions for omega(*)(m) using Floquet perturbation theory and numerically compute entanglement entropy, equal-time correlation functions, and density autocorrelation of fermions. All these quantities demonstrate clear signatures of strong HSF. We also investigate the fate of HSF as one deviates from omega(*)(m) and discuss the extent of the prethermal regime as a function of the drive amplitude.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Andre Neves Ribeiro
Summary: This paper analyzes the time evolution of a many-particle system starting from an out-of-equilibrium state with a fixed control parameter corresponding to a many-body energy-level crossing. Theorems regarding ergodicity, equilibration, and thermalization are proven. The occupancy of symmetrically equivalent basis states has different time-averaged probabilities under certain conditions. This nonergodicity remains in equilibrium. The paper also discusses the potential use of these findings in technology.
Article
Physics, Multidisciplinary
G. Zhang, Z. Song
Summary: We studied the impact of external fields on the energy level statistics and towers of eigenstates in spin-1/2 isotropic Heisenberg clusters. Different lattice structures were considered, including chain, ladder, square and triangular lattices. The presence of a uniform field in one direction allowed for a spectrum consisting mostly of towers with identical level spacing, thanks to the SU(2) symmetry. However, introducing random transverse fields in the other directions caused a transition from integrability to non-integrability, as evidenced by the change in level statistics from Poisson to Wigner-Dyson distributions. The largest tower still remained approximately intact even when the symmetry was broken, resulting in a quantum scar. Additionally, non-thermalized states, such as the Greenberger-Horn-Zeilinger and W states, were found to exhibit revival features while a Neel state decayed rapidly in dynamic processes. Several dynamic schemes for experimental detection were also proposed. Our findings suggest the potential for thermalization-immune quantum information processing in finite-sized spin clusters.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
Michael H. Kolodrubetz, Frederik Nathan, Snir Gazit, Takahiro Morimoto, Joel E. Moore
PHYSICAL REVIEW LETTERS
(2018)
Article
Materials Science, Multidisciplinary
Sthitadhi Roy, Michael Kolodrubetz, Nathan Goldman, Adolfo G. Grushin
Article
Multidisciplinary Sciences
William Berdanier, Michael Kolodrubetz, S. A. Parameswaran, Romain Vasseur
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2018)
Editorial Material
Multidisciplinary Sciences
Michael Kolodrubetz
Article
Physics, Applied
B. Foxen, J. Y. Mutus, E. Lucero, E. Jeffrey, D. Sank, R. Barends, K. Arya, B. Burkett, Yu Chen, Zijun Chen, B. Chiaro, A. Dunsworth, A. Fowler, C. Gidney, M. Giustina, R. Graff, T. Huang, J. Kelly, P. Klimov, A. Megrant, O. Naaman, M. Neeley, C. Neill, C. Quintana, P. Roushan, A. Vainsencher, J. Wenner, T. C. White, John M. Martinis
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2019)
Article
Physics, Multidisciplinary
Nathan Ng, Michael Kolodrubetz
PHYSICAL REVIEW LETTERS
(2019)
Article
Physics, Multidisciplinary
Frederik Nathan, Rongchun Ge, Snir Gazit, Mark Rudner, Michael Kolodrubetz
Summary: The study investigates a disordered one-dimensional fermionic system driven by two incommensurate frequencies, showing the support of a topological phase where energy transfers between the two driving modes at a quantized rate. The phase is protected by a combination of disorder-induced spatial and frequency localizations unique to quasiperiodically driven systems. It is demonstrated that a similar phase can be realized in a cavity-qubit system driven by two incommensurate modes.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Christopher Timms, Lukas M. Sieberer, Michael H. Kolodrubetz
Summary: The study examines the response of the anomalous Floquet insulator to time-dependent noise, finding that the system's topological properties remain quantized even in the presence of noise, attributed to an interplay between diffusion and blocking of edge state decay. The boundaries of the topological phase are determined numerically with spatial disorder and analytically in the limit of vanishing disorder, suggesting an interpretation of the system as a non-Hermitian Floquet topological phase.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Saeed Rahmanian Koshkaki, Michael H. Kolodrubetz
Summary: This paper studies energy-dependent localization in the disordered Ising model with global coupling to a d-level system. The authors discover an inverted mobility edge where high-energy states are localized and low-energy states are delocalized. They also discuss the critical energy of the localization phase transition and the existence of a reentrant many-body localization phase at lower energies.
Article
Materials Science, Multidisciplinary
Rong-Chun Ge, Michael Kolodrubetz
Summary: The goal is to realize novel phases of matter with topological order using superconducting circuits and other artificial quantum systems. By creating nearly flat topological bands on small lattices, it is possible to observe fingerprints of fractionalization through charge pumping with as few as 24 lattice sites. The proposal suggests using a finite lattice of superconducting qubits with cylindrical connectivity on triangular and square lattices to implement the concept.
Article
Materials Science, Multidisciplinary
Nathan Ng, Sebastian Wenderoth, Rajagopala Reddy Seelam, Eran Rabani, Hans-Dieter Meyer, Michael Thoss, Michael Kolodrubetz
Summary: This study investigates the dynamics of systems coupling a central degree of freedom with a bath, revealing a well-defined thermodynamic limit and scaling collapse behavior in the central qubit and spin system. The growth of entanglement at longer timescales may be attributed to dephasing mechanisms or long-range interactions mediated by the central degree of freedom. Signs of localization are also observed with unscaled system-bath coupling.
Article
Materials Science, Multidisciplinary
Jan Behrends, Sthitadhi Roy, Michael H. Kolodrubetz, Jens H. Bardarson, Adolfo G. Grushin
Article
Quantum Science & Technology
B. Foxen, J. Y. Mutus, E. Lucero, R. Graff, A. Megrant, Yu Chen, C. Quintana, B. Burkett, J. Kelly, E. Jeffrey, Yan Yang, Anthony Yu, K. Arya, R. Barends, Zijun Chen, B. Chiaro, A. Dunsworth, A. Fowler, C. Gidney, M. Giustina, T. Huang, P. Klimov, M. Neeley, C. Neill, P. Roushan, D. Sank, A. Vainsencher, J. Wenner, T. C. White, John M. Martinis
QUANTUM SCIENCE AND TECHNOLOGY
(2018)
Article
Materials Science, Multidisciplinary
Karthik Seetharam, Paraj Titum, Michael Kolodrubetz, Gil Refael
Article
Materials Science, Multidisciplinary
William Berdanier, Michael Kolodrubetz, S. A. Parameswaran, Romain Vasseur