Interaction-induced dynamical phase locking of Bose-Einstein condensates

TL;DR

Interactions between Bose-Einstein condensates can induce a stable relative phase, leading to universal interference fringe visibility in the Josephson regime, with coherence dynamics depending on initial conditions.

Contribution

This work demonstrates that interactions can generate a definite relative phase between initially incoherent condensates, revealing universal coherence behavior in the Josephson regime.

Findings

Universal fringe visibility at g_{12}^{(1)}~1/3 in the Josephson regime

Different incoherent initial states lead to distinct coherence dynamics

Interactions induce a stable relative phase between condensates

Abstract

We show that interactions result in the emergence of a {\it definite} relative-phase between two initially incoherent Bose-Einstein condensates. The many-realization interference fringe visibility is universal at $g_{12}^{(1)}\sim1/3$ throughout the Josephson interaction regime, as evident from a semiclassical picture. Other types of incoherent preparation yield qualitatively different coherence dynamics.