Resonant Light Scattering to Measure BEC-Pairing

TL;DR

This paper introduces a resonant light scattering method that reveals detailed information about Bose-Einstein condensates, including pairing density, surpassing traditional non-resonant techniques.

Contribution

It develops a formalism for resonant scattering that directly measures BEC pairing density, providing new insights into condensate symmetry and quantum state.

Findings

Resonant scattering accesses more information than the dynamical structure factor.

Detuning dependence allows direct measurement of BEC pairing density.

Method distinguishes broken symmetry in condensates.

Abstract

We present a single-scattering formalism for incoherent resonant light scattering by dilute quantum gas systems such as the atomic-trap Bose-Einstein condensates. We show that resonant scattering gives access to more information than the dynamical structure factor, familiar from non-resonant scattering. In particular, we show that the detuning dependence of the incoherent scattering cross-section allows the direct determination of the BEC pairing density $< \psi \psi >$, which is a broken symmetry and provides evidence that the condensate is not in a good number state.