Dynamical quantum phase transition of a two-component Bose-Einstein condensate in an optical lattice

TL;DR

This paper investigates the dynamical behavior of a two-component Bose-Einstein condensate in an optical lattice, focusing on the phase transition dynamics and the effects of interactions and trapping.

Contribution

It provides a detailed analysis of the dynamical quantum phase transition in a coupled BEC system, including the effects of non-linear interactions and external confinement.

Findings

Phase transition is resilient to contact interactions.

Adiabaticity breaks down near the critical point.

External trapping does not prevent the phase transition.

Abstract

We study dynamics of a two-component Bose-Einstein condensate where the two components are coupled via an optical lattice. In particular, we focus on the dynamics as one drives the system through a critical point of a first order phase transition characterized by a jump in the internal populations. Solving the time-dependent Gross-Pitaevskii equation, we analyze; breakdown of adiabaticity, impact of non-linear atom-atom scattering, and the role of a harmonic trapping potential. Our findings demonstrate that the phase transition is resilient to both contact interaction between atoms and external trapping confinement.