Vector solitons in a spin-orbit coupled spin-$2$ Bose-Einstein condensate

TL;DR

This paper investigates the properties of vector solitons in a spin-orbit-coupled spin-2 Bose-Einstein condensate, revealing two types of solutions with distinct symmetry and propagation characteristics through numerical and variational methods.

Contribution

It introduces a detailed analysis of multi-peak and single-peak vector solitons in a spin-2 BEC, highlighting their symmetry properties and dynamic behaviors, which were not previously characterized.

Findings

Multi-peak solitons preserve time-reversal symmetry but cannot propagate shape-maintaining.

Single-peak solitons violate time-reversal symmetry but can propagate with a constant shape.

Two distinct solution types are identified based on interaction parameters.

Abstract

Five-component minimum-energy bound states and mobile vector solitons of a spin-orbit-coupled quasi-one-dimensional hyperfine-spin-2 Bose-Einstein condensate are studied using the numerical solution and variational approximation of a mean-field model. Two distinct types of solutions with single-peak and multi-peak density distribution of the components are identified in different domains of interaction parameters. From an analysis of Galilean invariance and time-reversal symmetry of the Hamiltonian, we establish that vector solitons with multi-peak density distribution preserve time-reversal symmetry, but cannot propagate maintaining the shape of individual components. However, those with single-peak density distribution violate time-reversal symmetry of the Hamiltonian, but can propagate with a constant velocity maintaining the shape of individual components.