Collisional-inhomogeneity-induced generation of matter-wave dark solitons

TL;DR

This paper presents a method to generate and control matter-wave dark solitons in Bose-Einstein condensates by using spatially inhomogeneous interactions, with analysis of their stability and decay into vortices.

Contribution

It introduces a protocol for controlled dark soliton creation via inhomogeneous scattering length modulation in BECs, including two-dimensional effects and soliton decay mechanisms.

Findings

Controlled generation of dark solitons in quasi-1D BECs.

Decay of 2D solitons into vortex structures due to snaking instability.

Parameter dependence of soliton and vortex dynamics.

Abstract

We propose an experimentally relevant protocol for the controlled generation of matter-wave dark solitons in atomic Bose-Einstein condensates (BECs). In particular, using direct numerical simulations, we show that by switching-on a spatially inhomogeneous (step-like) change of the s-wave scattering length, it is possible to generate a controllable number of dark solitons in a quasi-one-dimensional BEC. A similar phenomenology is also found in the two-dimensional setting of "disk-shaped" BECs but, as the solitons are subject to the snaking instability, they decay into vortex structures. A detailed investigation of how the parameters involved affect the emergence and evolution of solitons and vortices is provided.