Damping in dilute Bose gases: a mean-field approach

TL;DR

This paper investigates damping mechanisms in dilute Bose gases using a mean-field approach, providing explicit formulas for Landau and Beliaev damping rates in non-uniform and uniform systems at various temperatures.

Contribution

It introduces a mean-field framework to calculate damping rates in dilute Bose gases, including explicit results for Landau and Beliaev damping in different regimes.

Findings

Explicit damping rates for non-uniform gases

Damping of phonons at zero and finite temperature

Discussion of isothermal compressibility

Abstract

Damping in a dilute Bose gas is investigated using a mean-field approximation which describes the coupled oscillations of condensate and non-condensate atoms in the collisionless regime. Explicit results for both Landau and Beliaev damping rates are given for non-uniform gases. In the case of uniform systems we obtain results for the damping of phonons both at zero and finite temperature. The isothermal compressibility of a uniform gas is also discussed.