Disorder-Driven Loss of Phase Coherence in a Quasi-2D Cold Atom System

TL;DR

This paper investigates how controllable disorder affects phase coherence in a quasi-2D ultracold atom system, revealing that disorder induces phase fluctuations while preserving the condensate amplitude, shedding light on superconductor-insulator transitions.

Contribution

It demonstrates that disorder causes phase fluctuations without amplitude suppression in a quasi-2D cold atom system, providing insights into phase-fluctuation mechanisms in disordered 2D superconductors.

Findings

Disorder induces phase fluctuations in the system.

Amplitude of the quasi-condensate remains largely unaffected.

Results are relevant to understanding superconductor-insulator transitions.

Abstract

We study the order parameter of a quasi-2D gas of ultracold atoms trapped in an optical potential in the presence of controllable disorder. Our results show that disorder drives phase fluctuations without significantly affecting the amplitude of the quasi-condensate order parameter. This is evidence that disorder can drive phase fluctuations in 2D systems, relevant to the phase-fluctuation mechanism for the superconductor-to-insulator phase transition (SIT) in disordered 2D superconductors.