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arXiv · 2208.09972

Soliton collisions in Bose-Einstein condensates with current-dependent interactions

Abstract

We study general collisions between chiral solitons in Bose-Einstein condensates subject to combined attractive and current-dependent interatomic interactions. A simple analysis based on the linear superposition of the solitons allows us to determine the relevant time and space scales of the dynamics, which is illustrated by extensive numerical simulations. By varying the differential amplitude, the relative phase, the average velocity, and the relative velocity of the solitons, we characterize the different dynamical regimes that give rise to oscillatory and interference phenomena. Apart from the known inelastic character of the collisions, we show that the chiral dynamics involves an amplitude reduction with respect to the case of regular solitons. To compare with feasible ultracold gas experiments, the influence of harmonic confinement is analyzed in both the emergence and the interaction of chiral solitons.

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Qian Jia, Haibo Qiu, Antonio Muñoz Mateo. 2022-08-21. Soliton collisions in Bose-Einstein condensates with current-dependent interactions. https://doi.org/10.1103/physreva.106.063314

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