Gap solitons in optical lattices embedded into nonlocal media

TL;DR

This paper investigates the behavior of gap solitons in optical lattices within nonlocal media, revealing their existence, stability, and mobility, and showing that nonlocality supports solitons even in quasi-linear regimes.

Contribution

It demonstrates that gap solitons can exist and remain stable in highly nonlocal, self-defocusing media, with variational approximation accurately predicting their properties.

Findings

Gap solitons exist in highly nonlocal media.

Variational approximation aligns well with numerical results.

Nonlocality supports solitons in quasi-linear regimes.

Abstract

We analyze the existence, stability, and mobility of gap solitons (GSs) in a periodic photonic structure built into a nonlocal self-defocusing medium. Counter-intuitively, the GSs are supported even by a highly nonlocal nonlinearity, which makes the system quasi-linear. Unlike local models, the variational approximation (VA) predicts the GSs in a good agreement with numerical findings, due to the suppression of undulating tails of the solitons.