Relation between irreversibility and entanglement in classically chaotic quantum kicked rotors

TL;DR

This paper explores how entanglement and irreversibility are related in chaotic quantum systems, revealing a strong correlation and critical fluctuations near a coupling threshold.

Contribution

It demonstrates a detailed correlation between entanglement entropy and classical decay times in quantum chaotic rotors, highlighting critical behavior at a coupling threshold.

Findings

Entanglement entropy correlates with classical decay of correlation.

Large fluctuations in entanglement near the coupling threshold.

Positive correlation between entanglement and eigenfunction lifetime.

Abstract

The relation between the degree of entanglement and time scale of time-irreversible behavior is investigated for classically chaotic quantum coupled kicked rotors by comparing the entanglement entropy (EE) and the lifetime of correspondence with classical decay of correlation, which was recently introduced. Both increase {\it on average} drastically with a strong correlation when the strength of coupling between the kicked rotors exceeds a certain threshold. The EE shows an anomalously large fluctuation resembling a critical fluctuation around the threshold value of coupling strength where the entanglement sharply increases toward full entanglement. In this regime it can be shown that, although the correlation is hidden, EE and the lifetime of {\it individual eigenfunctions} also have a positive correlation that can be seen via an another measure.