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There has been recent progress in understanding chaotic features in many-body quantum systems. Motivated by the scrambling of information in black holes, it has been suggested that the time dependence of out-of-time-ordered (OTO)…

Quantum Physics · Physics 2016-12-28 Guanyu Zhu , Mohammad Hafezi , Tarun Grover

We describe general features of thermal correlation functions in quantum systems, with specific focus on the fluctuation-dissipation type relations implied by the KMS condition. These end up relating correlation functions with different…

High Energy Physics - Theory · Physics 2018-01-03 Felix M. Haehl , R. Loganayagam , Prithvi Narayan , Amin A. Nizami , Mukund Rangamani

The scrambling of quantum information in closed many-body systems, as measured by out-of-time-ordered correlation functions (OTOCs), has lately received considerable attention. Recently, a hydrodynamical description of OTOCs has emerged…

Statistical Mechanics · Physics 2018-09-12 Tibor Rakovszky , Frank Pollmann , C. W. von Keyserlingk

Out-of-time-order correlators (OTOCs) can be used to probe how quickly a quantum system scrambles information when the initial conditions of the dynamics are changed. In sufficiently large quantum systems, one can extract from the OTOC the…

Chemical Physics · Physics 2022-03-31 Chenghao Zhang , Peter G. Wolynes , Martin Gruebele

The out-of-time-ordered correlator (OTOC) has emerged as an interesting object in both classical and quantum systems for probing the spatial spread and temporal growth of initially local perturbations in spatially extended chaotic systems.…

Statistical Mechanics · Physics 2023-11-21 Dipankar Roy , David A. Huse , Manas Kulkarni

There is a remarkable interest in the study of Out-of-time ordered correlators (OTOCs) that goes from many body theory and high energy physics to quantum chaos. In this latter case there is a special focus on the comparison with the…

Quantum Physics · Physics 2019-10-30 Pablo D. Bergamasco , Gabriel G. Carlo , Alejandro M. F. Rivas

A detailed numerical study reveals that the asymptotic values of the standard deviation-to-mean ratio of the out-of-time-ordered correlator can be successfully used as a measure of the quantum chaoticity of the system. We employ a…

Quantum Physics · Physics 2023-05-30 Jakub Novotný , Pavel Stránský

The relaxation of out-of-time-ordered correlators (OTOCs) has been studied as a mean to characterize the scrambling properties of a quantum system. We show that the presence of local conserved quantities typically results in, at the…

Statistical Mechanics · Physics 2021-09-22 Vinitha Balachandran , Giuliano Benenti , Giulio Casati , Dario Poletti

The growth of information scrambling, captured by out-of-time-order correlation functions (OTOCs), is a central indicator of the nature of many-body quantum dynamics. Here, we compute analytically the complete time dependence of the OTOC…

High Energy Physics - Theory · Physics 2025-11-21 Antonio M. García-García , Chang Liu , Lucas Sá , Jacobus J. M. Verbaarschot , Jie-ping Zheng

Out-of-time-order correlation functions (OTOCs) and their higher-order generalizations present important probes of quantum information dynamics and scrambling. We introduce a solvable many-body quantum model, which we term boundary…

Quantum Physics · Physics 2025-09-11 Felix Fritzsch , Gabriel O. Alves , Michael A. Rampp , Pieter W. Claeys

For systems of controllable qubits, we provide a method for experimentally obtaining a useful class of multitime correlators using sequential generalized measurements of arbitrary strength. Specifically, if a correlator can be expressed as…

In this work, we derive an exact hydrodynamical description for the coupled, charge and operator dynamics, in a quantum many-body system with U(1) symmetry. Using an emergent symmetry in the complex Brownian SYK model with charge…

Strongly Correlated Electrons · Physics 2023-05-12 Lakshya Agarwal , Subhayan Sahu , Shenglong Xu

Out of time ordered correlator (OTOC) is recently introduced as a powerful diagnose for quantum chaos. To go beyond, here we present an analytical solution of OTOC for a non-chaotic many body localized (MBL) system, showing distinct feature…

Disordered Systems and Neural Networks · Physics 2016-08-30 Yu Chen

Discretizing the $\lambda \phi^4$ scalar field theory on a lattice yields a system of coupled anharmonic oscillators with quadratic and quartic potentials. We begin by analyzing the two coupled oscillators in the second quantization method…

High Energy Physics - Theory · Physics 2026-05-12 Wung-Hong Huang

We study the connections between three quantities that can be used as diagnostics for quantum chaos, i.e., the out-of-time-order correlator (OTOC), Loschmidt echo (LE), and complexity. We generalize the connection between OTOC and LE for…

High Energy Physics - Theory · Physics 2022-02-04 Arpan Bhattacharyya , Wissam Chemissany , S. Shajidul Haque , Bin Yan

The dynamical generation of complex correlations in quantum many-body systems is of renewed interest in the context of quantum chaos, where the out-of-time-ordered (OTO) correlation function appears as a convenient measure of scrambling. To…

Quantum Physics · Physics 2018-07-25 Adrian Chapman , Akimasa Miyake

The question of how swiftly entanglement spreads over a system has attracted vital interest. In this regard, the out-of-time ordered correlator (OTOC) is a quantitative measure of the entanglement spreading process. Particular interest…

Quantum Physics · Physics 2022-02-08 A. K. Singh , Kushagra Sachan , L. Chotorlishvili , Vipin V. , Sunil K. Mishra

In this paper we numerically calculate the out-of-time-order correlation functions in the one-dimensional Bose-Hubbard model. Our study is motivated by the conjecture that a system with Lyapunov exponent saturating the upper bound…

Quantum Gases · Physics 2017-08-21 Huitao Shen , Pengfei Zhang , Ruihua Fan , Hui Zhai

We show that out-of-time-order correlators (OTOCs) constitute a probe for Local-Operator Entanglement (LOE). There is strong evidence that a volumetric growth of LOE is a faithful dynamical indicator of quantum chaos, while OTOC decay…

Quantum Physics · Physics 2023-11-06 Neil Dowling , Pavel Kos , Kavan Modi

In this paper we investigate measures of chaos and entanglement in rational conformal field theories in 1+1 dimensions. First, we derive a universal formula for the late time value of the out-of-time-ordered correlators for this class of…

High Energy Physics - Theory · Physics 2017-07-20 Pawel Caputa , Tokiro Numasawa , Alvaro Veliz-Osorio