Phase diffusion of Bose-Einstein condensates in a one-dimensional optical lattice

TL;DR

This paper studies how phase diffusion occurs in a Bose-Einstein condensate within a 1D optical lattice, proposing an experimental detection method via interference pattern analysis.

Contribution

It demonstrates that phase diffusion in a BEC in a 1D optical lattice can be observed through interference pattern measurements after lattice switch-off.

Findings

Phase diffusion is evident in the interference patterns.

Maximum density of interference pattern decreases due to phase diffusion.

Proposes an experimental method to detect phase diffusion in BECs.

Abstract

We investigate the phase diffusion of a Bose-Einstein condensate (BEC) confined in the combined potential of a magnetic trap and a one-dimensional optical lattice. We show that the phase diffusion of the condensate in the whole optical lattice is evident and can be measured from the interference pattern of expanding subcondensates after the optical lattice is switched off. The maximum density of the interference pattern decreases significantly due to the mixing of the phase diffusion appearing in different subcondensates. This suggests a way to detect experimentally the notable phase diffusion of BECs.