Interference effect of critical ultra-cold atomic Bose gases

TL;DR

This paper proposes a theoretical method using Kapitza-Dirac scattering to enhance and observe the critical correlation behavior in ultra-cold atomic Bose gases near the phase transition, facilitating the study of universal critical phenomena.

Contribution

It introduces a novel interference-based approach to detect critical correlations in ultra-cold Bose gases, enabling extraction of critical exponents from interference fringes.

Findings

Kapitza-Dirac scattering enhances interference effects near criticality.

Numerical rules allow extraction of critical exponents from interference patterns.

The method offers a new experimental tool for studying critical behavior in ultra-cold gases.

Abstract

For ultra-cold atomic gases close to the critical temperature, there is a divergent correlation behavior within the critical regime. This divergent correlation behavior is the cornerstone of the universal behavior within the critical regime, e.g. the universal critical exponent for the same class with very different physical systems. It is still quite challenging to observe this divergent correlation behavior in experiments with ultra-cold atomic gases. Here we consider theoretically the interference effect of the critical atomic Bose gas by a Kapitza-Dirac scattering. We find that the Kapitza-Dirac scattering has the merit of enhancing the interference effect in the observation of the correlation behavior. This provides a potential method to study the critical behavior of ultra-cold Bose gases. A simple rule is found by numerical simulations to get the critical exponent and correlation amplitude ratio from the interference fringes after the Kapitza-Dirac scattering.