Eur. Phys. J. Plus (2020) 135: 546
https://doi.org/10.1140/epjp/s13360-020-00544-z

Regular Article

Transverse dynamics of vector solitons in defocusing nonlocal media

¹ Department of Physics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15784, Athens, Greece
² Department of Mathematics, University of Ioannina, 45110, Ioannina, Greece
³ Department of Mathematics, State University of New York at Buffalo, 14260, Buffalo, NY, USA

^b horikis@uoi.gr

Received: 17 March 2020
Accepted: 17 June 2020
Published online: 6 July 2020

Abstract

The transverse instability of line solitons of a multicomponent nonlocal defocusing nonlinear Schrödinger (NLS) system is utilized to construct lump and vortex-like structures in 2D nonlocal media, such as nematic liquid crystals. These line solitons are found by means of a perturbation expansion technique, which reduces the nonintegrable vector NLS model to a completely integrable scalar one, namely to a Kadomtsev–Petviashvili equation. It is shown that dark or antidark soliton stripes, as well as dark lumps, are possible depending on the strength of nonlocality: dark (antidark) solitons are formed for weaker (stronger) nonlocality, relatively to a threshold that is analytically determined in terms of the parameters of the system and the continuous-wave amplitude. Direct numerical simulations are used to show that dark lump-like- and vortex-like-structures can spontaneously be formed as a result of the transverse instability of the dark soliton stripes.