Motion of solitons in one-dimensional spin-orbit-coupled Bose-Einstein condensates

TL;DR

This paper investigates how spin-orbit coupling affects the motion and spin dynamics of solitons in one-dimensional Bose-Einstein condensates, revealing unique oscillatory behaviors influenced by SOC, Raman coupling, and nonlinearity.

Contribution

It demonstrates the influence of spin-orbit coupling on soliton dynamics, governed by a nonlinear Bloch equation, with analytical and numerical validation.

Findings

Soliton spin dynamics follow a nonlinear Bloch equation.

Solitons exhibit oscillations with frequencies dependent on SOC, Raman coupling, and nonlinearity.

The study combines analytical and numerical methods to confirm the effects of SOC on soliton motion.

Abstract

Solitons play a fundamental role in dynamics of nonlinear excitations. Here we explore the motion of solitons in one-dimensional uniform Bose-Einstein condensates subjected to a spin-orbit coupling (SOC). We demonstrate that the spin dynamics of solitons is governed by a nonlinear Bloch equation. The spin dynamics influences the orbital motion of the solitons leading to the spin-orbit effects in the dynamics of the macroscopic quantum objects (mean-field solitons). The latter perform oscillations with a frequency determined by the SOC, Raman coupling, and intrinsic nonlinearity. These findings reveal unique features of solitons affected by the SOC, which is confirmed by analytical considerations and numerical simulations of the underlying Gross-Pitaevskii equations.