Dynamical Trapping of Matter-Wave Bright Solitons in Optical Lattices

Abstract

In this thesis, we investigate the dynamics of quasi-one-dimensional (Q1D) bright solitons in weakly coupled Bose-Einstein Condensates. The resulting dynamical regimes including Josephson-like oscillations and macroscopic quantum self-trapping (MQST) of solitons depend critically on the relative strengths of linear coupling and nonlinear interactions, mass imbalance, and the relative phase. We focus on a specific setup where bright soliton(s) traveling in a quasi-1D tube encounter a finite region where the coupling between the neighboring tubes is turned on, which leads to very interesting localization dynamics. Depending on the shape of the coupling region, the initial velocity, and the dynamical regime, we observe the dynamical trapping of the solitons within this coupling region. We characterize the nature of this trapping and describe the effective potential responsible using variational methods. We further propose an experimental setup for its realization and discuss the scope of applications of such trapping in experiments.