Dynamical phase diagram of a one dimensional Bose gas in a box with a tunable weak-link: from Bose-Josephson oscillations to shock waves

TL;DR

This paper investigates the dynamical behavior of a one-dimensional Bose gas in a box with a tunable weak-link, revealing regimes from Josephson oscillations to shock waves and identifying self-trapping phenomena through theoretical and experimental considerations.

Contribution

It provides a comprehensive analysis of the dynamical regimes in a 1D Bose gas with a tunable barrier, combining models and experimental protocols to explore complex phenomena.

Findings

Two-mode model accurately describes large barrier dynamics.

Dispersive shock waves and solitons emerge at low barriers.

Self-trapping resonances can be induced and understood qualitatively.

Abstract

We study the dynamics of one-dimensional bosons trapped in a box potential, in the presence of a barrier creating a tunable weak-link, thus realizing a one dimensional Bose Josephson junction. By varying the initial population imbalance and the barrier height we evidence different dynamical regimes. In particular we show that at large barriers a two mode model captures accurately the dynamics, while for low barriers the dynamics involves dispersive shock waves and solitons. We study a quench protocol that can be readily implemented in experiments and show that self-trapping resonances can occur. This phenomenon can be understood qualitatively within the two-mode model.