Superradiant Raman scattering in an ultracold Bose gas at finite temperature

TL;DR

This paper investigates superradiant Raman scattering in an ultracold Bose gas at finite temperature, revealing distinct decoherence timescales for condensed and thermal atoms, and showing that scattering can modestly cool the atoms.

Contribution

It provides numerical insights into how superradiant scattering depends on trap states and temperature, highlighting the different decoherence dynamics of condensed and thermal fractions.

Findings

Distinct timescales for decoherence of condensate and thermal atoms

Preferred scattering from low-lying trap states during superradiance

Scattered atoms experience a modest temperature reduction

Abstract

We study superradiant Raman scattering from an ultra-cold, but finite temperature Bose gas in a harmonic trap. Numerical simulations indicate the existence of distinct timescales associated with the decoherence of the condensed versus thermal fractions, and the concomitant preferred scattering from atoms in low lying trap states in the regime where superradiance takes place on a timescale comparable to an inverse trap frequency. As a consequence the scattered atoms experience a modest reduction in temperature as compared to the unscattered atoms.