Dynamics of entanglement entropy of interacting fermions in a 1D driven harmonic trap

TL;DR

This paper investigates how entanglement entropy evolves in interacting fermions confined in a one-dimensional harmonic trap under parametric resonance, revealing the effects of interactions and subsystem restrictions on thermalization.

Contribution

It extends previous studies by analyzing entanglement dynamics in multi-fermion systems under parametric driving, highlighting the impact of interactions and subsystem limitations.

Findings

Resonance imprints on entanglement entropy are clearly observed.

Interactions modify the entanglement signal in predictable ways.

Subsystem restriction induces locally thermal behavior.

Abstract

Following up on a recent analysis of two cold atoms in a time-dependent harmonic trap in one dimension, we explore the entanglement entropy of two and three fermions in the same situation when driven through a parametric resonance. We find that the presence of such a resonance in the two-particle system leaves a clear imprint on the entanglement entropy. We show how the signal is modified by attractive and repulsive contact interactions, and how it remains present for the three-particle system. Additionaly, we extend the work of recent experiments to demonstrate how restricting observation to a limited subsystem gives rise to locally thermal behavior.