Multidimensional Josephson vortices in spin-orbit coupled Bose-Einstein condensates: snake instability and decay through vortex dipoles

TL;DR

This paper investigates the behavior and stability of Josephson vortices in spin-orbit coupled Bose-Einstein condensates, revealing stable configurations and decay mechanisms like snake instability and vortex dipole formation.

Contribution

It provides the first detailed analysis of multidimensional Josephson vortices in spin-orbit coupled BECs, including their stability regimes and decay dynamics.

Findings

Stable Josephson vortices exist in multidimensional systems under typical experimental conditions.

Snake instability leads to vortex dipole formation in disk-shaped condensates.

The dynamics of vortices depend on their orientation relative to the spin-orbit coupling.

Abstract

We analyze the dynamics of Josephson vortex states in two-component Bose-Einstein condensates with Rashba-Dresselhaus spin-orbit coupling by using the Gross-Pitaevskii equation. In 1D, both in homogeneous and harmonically trapped systems, we report on stationary states containing doubly charged, static Josephson vortices. In multidimensional systems, we find stable Josephson vortices in a regime of parameters typical of current experiments with $^{87}$Rb atoms. In addition, we discuss the instability regime of Josephson vortices in disk-shaped condensates, where the snake instability operates and vortex dipoles emerge. We study the rich dynamics that they exhibit in different regimes of the spin-orbit coupled condensate depending on the orientation of the Josephson vortices.