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The out-of-time-order correlator (OTOC) has emerged as a central tool for quantifying decoherence across wide-ranging physical platforms. Here we demonstrate its direct measurement in a classical ensemble using nuclear magnetic resonance…

Out-of-time-order correlators (OTOCs) have been proposed as sensitive probes for chaos in interacting quantum systems. They exhibit a characteristic classical exponential growth, but saturate beyond the so-called scrambling or Ehrenfest…

Statistical Mechanics · Physics 2018-09-25 Josef Rammensee , Juan-Diego Urbina , Klaus Richter

This letter reports the findings of the late time behavior of the out-of-time-ordered correlators (OTOCs) via a quantum kicked rotor model with $\cal{PT}$-symmetric driving potential. An analytical expression of the OTOCs' quadratic growth…

Quantum Physics · Physics 2021-06-01 Wen-Lei Zhao

We construct an effective field theory (EFT) that captures the universal behavior of out-of-time-order correlators (OTOCs) at late times in generic quantum many-body systems with conservation laws. The EFT hinges on a generalization of the…

Strongly Correlated Electrons · Physics 2026-02-12 Ruchira Mishra , Jiaozi Wang , Silvia Pappalardi , Luca V. Delacrétaz

The out-of-time-order correlator (OTOC) is considered as a measure of quantum chaos. We formulate how to calculate the OTOC for quantum mechanics with a general Hamiltonian. We demonstrate explicit calculations of OTOCs for a harmonic…

High Energy Physics - Theory · Physics 2017-11-22 Koji Hashimoto , Keiju Murata , Ryosuke Yoshii

Out-of time-ordered correlators (OTOC) have recently attracted significant attention from the physics of many-body systems, to quantum black-holes, with an exponential growth of the OTOC indicating quantum chaos. Here we consider OTOC in…

Quantum Physics · Physics 2019-07-03 Sivaprasad Omanakuttan , Arul Lakshminarayan

Out-of-Time-Order Correlators (OTOCs) serve as a proxy for quantum information scrambling, which refers to the process where information stored locally disperses across the many-body degrees of freedom in a quantum system, rendering it…

We study out-of-time order correlators (OTOCs) of the form $\langle\hat A(t)\hat B(0)\hat C(t)\hat D(0)\rangle$ for a quantum system weakly coupled to a dissipative environment. Such an open system may serve as a model of, e.g., a small…

Mesoscale and Nanoscale Physics · Physics 2018-05-02 S. V. Syzranov , A. V. Gorshkov , V. Galitski

Exact solutions for local equilibrium and nonequilibrium out-of-time-ordered correlation (OTOC) functions are obtained for a lattice fermion model with on-site interactions, namely the Falicov-Kimball (FK) model, in the large dimensional…

Quantum Gases · Physics 2017-02-13 Naoto Tsuji , Philipp Werner , Masahito Ueda

In classical dynamical systems, chaotic behavior is often associated with exponential sensitivity to initial conditions together with global phase-space structure. Translating this geometric concept to the strictly linear framework of…

Quantum Physics · Physics 2026-03-24 Stephen Wiggins

The out-of-time-ordered correlator (OTOC) is a measure of quantum chaos that is being vigorously investigated. Analytically accessible simple models that have long been studied in other contexts could provide insights into such measures.…

Quantum Physics · Physics 2019-01-09 Arul Lakshminarayan

Motivated by the famous ink-drop experiment, where ink droplets are used to determine the chaoticity of a fluid, we propose an experimentally implementable method for measuring the scrambling capacity of quantum processes. Here, a system of…

Quantum Physics · Physics 2023-07-19 Magdalini Zonnios , Jesper Levinsen , Meera M. Parish , Felix A. Pollock , Kavan Modi

In recent years, the out-of-time-order correlator (OTOC) has emerged as a diagnostic tool for information scrambling in quantum many-body systems. Here, we present exact analytical results for the OTOC for a typical pair of random local…

Quantum Physics · Physics 2021-01-22 Georgios Styliaris , Namit Anand , Paolo Zanardi

Quantum scrambling is the dispersal of local information into many-body quantum entanglements and correlations distributed throughout the entire system. This concept underlies the dynamics of thermalization in closed quantum systems, and…

We provide an exact evaluation of the out-of-time correlation (OTOC) functions for the localized $f$-particle states in the Falicov-Kimball model within dynamical mean-field theory. Different regimes of quantum chaos and quantum scrambling…

Strongly Correlated Electrons · Physics 2026-01-07 A. M. Shvaika , J. K. Freericks

Generic systems are associated with a mixed classical phase space.The question of the properties of the eigenstates for these systems remains less known, although it plays a key role for understanding several important quantum phenomena…

Quantum Physics · Physics 2025-03-04 Qian Wang , Marko Robnik

Recently, the out-of-time-ordered correlator (OTOC) has gained much attention as an indicator of quantum chaos. In the semi-classical limit, its exponential growth rate resembles the classical Lyapunov exponent. The quantum-classical…

Quantum Physics · Physics 2023-10-26 Devvrat Tiwari , Subhashish Banerjee

In this paper, the out-of-time-order correlators (OTOC) in quantum harmonic oscillators are calculated analytically by second quantization method in perturbative approximation. We consider the coupled harmonic oscillators and anharmonic…

High Energy Physics - Theory · Physics 2023-08-21 Wung-Hong Huang

Quantum dynamics is of fundamental interest and has implications in quantum information processing. The four-point out-of-time-ordered correlator (OTOC) is traditionally used to quantify quantum information scrambling under many-body…

Quantum Physics · Physics 2021-12-06 Roy J. Garcia , You Zhou , Arthur Jaffe

Out-of-time-order correlators (OTOC) are considered to be a promising tool to characterize chaos in quantum systems. In this paper we study OTOC in XY model. With the presence of anisotropic parameter $\gamma$ and external magnetic field…

Statistical Mechanics · Physics 2020-08-26 Jiahui Bao , Cheng-Yong Zhang