Dipole Oscillations of a Fermi Gas in a Disordered Trap: Damping and Localization

TL;DR

This paper investigates how disorder affects the dipole oscillations of a Fermi gas, revealing a transition from damping due to dephasing to strong damping caused by localization, indicating a metal-insulator crossover.

Contribution

It provides a theoretical analysis of damping mechanisms and identifies the disorder-induced metal-insulator transition in a Fermi gas within a disordered trap.

Findings

Weak disorder causes damping via dephasing.

Increasing disorder leads to localization and strong damping.

A crossover from metallic to insulating behavior is identified.

Abstract

We theoretically study the dipole oscillations of an ideal Fermi gas in a disordered trap. We show that even weak disorder induces strong damping of the oscillations and we identify a metal-insulator crossover. For very weak disorder, we show that damping results from a dephasing effect related to weak random perturbations of the energy spectrum. For increasing disorder, we show that the Fermi gas crosses over to an insulating regime characterized by strong-damping due to the proliferation of localized states.