Nonergodic Behavior of Interacting Bosons in Harmonic Traps

TL;DR

This paper investigates the nonergodic dynamics of interacting bosons in harmonic traps, revealing conditions under which quantum systems exhibit ergodic behavior despite low-energy fluctuations.

Contribution

It identifies specific conditions that guarantee ergodicity in quantum bosonic systems below the condensation temperature.

Findings

Quantum systems are nonergodic at low energies with large ground state fluctuations.

Nonergodic behavior persists at high energies for modest particle numbers.

Two conditions are proposed to ensure ergodicity below the condensation temperature.

Abstract

We study the time evolution of a system of interacting bosons in a harmonic trap. In the low-energy regime, the quantum system is not ergodic and displays rather large fluctuations of the ground state occupation number. In the high energy regime of classical physics we find nonergodic behavior for modest numbers of trapped particles. We give two conditions that assure the ergodic behavior of the quantum system even below the condensation temperature.