# Out-of-time-ordered correlation functions in open systems: A Feynman-Vernon influence functional approach

@article{Tuziemski2019OutoftimeorderedCF, title={Out-of-time-ordered correlation functions in open systems: A Feynman-Vernon influence functional approach}, author={Jan Tuziemski}, journal={Physical Review A}, year={2019} }

Recent theoretical and experimental studies have shown the significance of quantum information scrambling (i.e., the spread of quantum information over a system's degrees of freedom) for problems e ...

## 10 Citations

THE GENERALIZED OTOC FROM SUPERSYMMETRIC QUANTUM MECHANICS: Study of Random Fluctuations from Eigenstate Representation of Correlation Functions

- Physics
- 2020

The concept of out-of-time-ordered correlation (OTOC) function is treated as a very strong theoretical probe of quantum randomness, using which one can study both chaotic and non-chaotic phenomena in…

Dynamics of quantum information scrambling under decoherence effects measured via active spin clusters

- PhysicsPhysical Review A
- 2021

Developing quantum technologies requires the control and understanding of the non-equilibrium dynamics of quantum information in many-body systems. Local information propagates in the system by…

Complexity from the reduced density matrix: a new diagnostic for chaos

- Physics, Computer ScienceJournal of High Energy Physics
- 2021

It is demonstrated that the evolution of complexity is a possible diagnostic of chaos through explicit calculations on a toy model of two coupled harmonic oscillators, where one or both of the oscillators are inverted.

Classical and quantum chaos in chirally-driven, dissipative Bose-Hubbard systems

- Physics
- 2022

We study the dissipative Bose-Hubbard model on a small ring of sites in the presence of a chiral drive and explore its long-time dynamical structure using the mean-field equations and by simulating…

Entanglement Phase Transitions in Measurement-Only Dynamics

- Physics, Economics
- 2020

Unitary circuits subject to repeated projective measurements can undergo an entanglement transition as a function of the measurement rate. This transition is generally understood in terms of a…

Information Scrambling and Loschmidt Echo.

- PhysicsPhysical review letters
- 2020

Analytically and numerically, the out-of-time order correlator is demonstrated to be given by the thermal average of Loschmidt echo signals, a well-appreciated familiar diagnostic that captures the dynamical aspect of chaotic behavior in the time domain and is accessible to experimental studies.

Out-of-time-order correlations in the quasiperiodic Aubry-André model

- PhysicsPhysical Review B
- 2020

We study out-of-time-ordered correlators (OTOC) in a free fermionic model with a quasiperiodic potential. This model is equivalent to the Aubry-Andr\'e model and features a phase transition from an…

Out-of-time-order correlator in weakly perturbed integrable systems

- Physics, Mathematics
- 2019

Classical quasi-integrable systems are known to have Lyapunov times much shorter than their ergodicity time, but the situation for their quantum counterparts is less well understood. As a first…

Quasi-integrable systems are slow to thermalize but may be good scramblers.

- PhysicsPhysical review. E
- 2020

The quantum Lyapunov exponent, defined by the evolution of the four-point out-of-time-order correlator (OTOC), of integrable systems which are weakly perturbed by an external noise is examined, a setting that has proven to be illuminating in the classical case.

Scaling at the OTOC Wavefront: Integrable versus chaotic models

- Physics
- 2021

Out of time ordered correlators (OTOCs) are useful tools for investigating foundational questions such as thermalization in closed quantum systems because they can potentially distinguish between…

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- Physics
- 2018

Two topics, evolving rapidly in separate fields, were combined recently: the out-of-time-ordered correlator (OTOC) signals quantum-information scrambling in many-body systems. The Kirkwood-Dirac (KD)…

Scrambling of quantum information in quantum many-body systems

- Physics
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