Classical route to ergodicity and scarring in collective quantum systems

TL;DR

This paper reviews the relationship between ergodicity, chaos, and quantum scarring in collective quantum systems, highlighting recent theoretical and experimental progress and providing tools for their analysis.

Contribution

It offers a comprehensive overview connecting classical chaos with quantum phenomena like scarring in collective quantum systems, emphasizing the classical perspective.

Findings

Quantum scarring causes deviations from ergodicity in quantum systems.

Recent experimental evidence supports the classical-quantum connection in chaos.

Tools for detecting chaos and scarring are summarized and discussed.

Abstract

Ergodicity, a fundamental concept in statistical mechanics, is not yet a fully understood phenomena for closed quantum systems, particularly its connection with the underlying chaos. In this review, we consider a few examples of collective quantum systems to unveil the intricate relationship of ergodicity as well as its deviation due to quantum scarring phenomena with their classical counterpart. A comprehensive overview of classical and quantum chaos is provided, along with the tools essential for their detection. Furthermore, we survey recent theoretical and experimental advancements in the domain of ergodicity and its violations. This review aims to illuminate the classical perspective of quantum scarring phenomena in interacting quantum systems.