Large transverse shifts appearing upon passage of vortices through oblique dark solitons

TL;DR

This paper investigates how vortices experience significant vertical shifts when passing through oblique dark solitons in a Kerr medium, revealing dependencies on inclination angle and flow velocity, with analytical estimates and observations of similar effects in related vortex interactions.

Contribution

It introduces the phenomenon of large transverse vortex shifts during collision with oblique dark solitons and provides analytical estimates for this effect in Kerr-type media.

Findings

Vortices undergo large vertical shifts upon passing through oblique dark solitons.

The shift depends on the inclination angle and flow velocity.

Similar effects are observed with vortex dipoles and rotating vortex pairs.

Abstract

We show that when a single vortex convected by a flowing background collides with an oblique dark soliton in defocusing Kerr-type medium, it passes through the oblique soliton, but this process is accompanied by a considerable vertical shift of the vortex that grows with decrease of the inclination angle of the dark soliton with respect to the direction of the flow and decreases with increase of the flow (or collision) velocity. In the parameter range where the interaction with a vortex does not lead to drastic deformations of the shape of the oblique dark soliton, this shift can be estimated analytically under the assumption that vortex soliton moves along the "stream lines" that exhibit vertical shift in the vicinity of oblique dark soliton. Similar effect was observed upon collision of dark solitons with moving vortex dipoles or rotating pairs of vortices with equal topological charges.