Yang-Yang thermodynamics on an atom chip

TL;DR

This paper demonstrates that the Yang-Yang thermodynamic formalism accurately describes the behavior of a weakly interacting 1D Bose gas at finite temperature on an atom chip, validated through in situ density measurements and momentum distribution analysis.

Contribution

It provides experimental validation of the Yang-Yang thermodynamics for a 1D Bose gas, outperforming approximate models in this regime.

Findings

Density profiles match Yang-Yang model predictions

Momentum distribution agrees with in situ measurements

Validates exact thermodynamic solutions for 1D Bose gases

Abstract

We investigate the behavior of a weakly interacting nearly one-dimensional (1D) trapped Bose gas at finite temperature. We perform in situ measurements of spatial density profiles and show that they are very well described by a model based on exact solutions obtained using the Yang-Yang thermodynamic formalism, in a regime where other, approximate theoretical approaches fail. We use Bose-gas focusing [Shvarchuck etal., Phys. Rev. Lett. 89, 270404 (2002)] to probe the axial momentum distribution of the gas, and find good agreement with the in situ results.