Stable Optical Vortex Solitons in Pair Plasmas

TL;DR

This paper demonstrates that pair plasmas with slight temperature differences can support stable optical vortex solitons, with stability depending on amplitude and charge, due to a unique focusing-defocusing nonlinear response.

Contribution

It reveals the existence and stability conditions of localized and delocalized optical vortex solitons in pair plasmas with saturating nonlinearities.

Findings

Delocalized vortex solitons are stable throughout their existence range.

Localized vortex solitons are unstable at low amplitudes and stable at relativistic amplitudes.

The nonlinear response exhibits focusing-defocusing behavior depending on amplitude.

Abstract

It is shown that the pair plasmas with small temperature asymmetry can support existence of localized as well as de-localized optical vortex solitons. Coexistence of such solitons is possible due to peculiar form of saturating nonlinearity which has a focusing-defocusing nature -- for weak amplitudes being focusing becoming defocusing for higher amplitudes. It is shown that delocalized vortex soliton is stable in entire region of its existence while single- and multi-charged localized vortex solitons are unstable for low amplitudes and become stable for relativistic amplitudes.