Persistent revivals in a system of trapped bosonic atoms

TL;DR

This paper investigates quantum chaos in trapped bosonic atoms, revealing that certain initial states exhibit long-lasting revivals linked to quantum scarring, especially in the chaotic energy region.

Contribution

It demonstrates the presence of quantum chaos and revivals in a cold atom system, highlighting the role of participation ratio and quantum scarring in long-time dynamics.

Findings

States with large PR show correlation holes before equilibration.

States with small PR exhibit revivals up to equilibration.

Chaos is observed at small disorder and intermediate energies.

Abstract

Dynamical signatures of quantum chaos are observed in the survival probability of different initial states, in a system of cold atoms trapped in a linear chain with site noise and open boundary conditions. It is shown that chaos is present in the region of small disorder, at intermediate energies. The study is performed with different number of sites and atoms: 7,8 and 9, but focusing on the case where the particle density is one. States of the occupation basis with energies in the chaotic region are evolved at long times. Remarkable differences in the behaviour of the survival probability are found for states with different energy-eigenbasis participation ratio (PR). Whereas those with large PR clearly exhibit the characteristic random-matrix correlation hole before equilibration, those with small PR present a marginal or even no correlation hole which is replaced by revivals lasting up to the stage of equilibration, suggesting a connection with the quantum scarring phenomenon.