Josephson Oscillation and Nonlinear Self-Trapping in Quasi-one-dimensional Quantum Liquid

TL;DR

This paper investigates Josephson oscillations and nonlinear self-trapping in a quasi-one-dimensional binary Bose-Einstein condensate, incorporating beyond mean-field effects and three-body interactions, using a two-mode approach and Bogoliubov analysis.

Contribution

It introduces a detailed analysis of Josephson dynamics in a binary BEC considering beyond mean-field and three-body effects, with quantitative insights into asymmetry and dimensional influences.

Findings

Identification of regions of dynamical instability.

Observation of roton-like modes in the excitation spectrum.

Quantitative effects of asymmetry on oscillation and trapping.

Abstract

In this article, we study the two-mode method to analyze the Josephson oscillation for a trapped binary Bose-Einstein condensate while taking into account the beyond mean-field and three body interactions. For this purpose, we use the archetypal model of double well potential and study the Josephson oscillation and self-trapping phases in quasi-one dimension. Additionally, our analysis provides quantitative discussion on the effect of asymmetry and dimension. We further corroborate our findings with Bogoliubov quasi-particle method and notice regions of instabilities and roton like mode.