Surface solitons at interfaces of arrays with spatially-modulated nonlinearity

TL;DR

This paper investigates two-dimensional surface solitons at waveguide array interfaces with periodically modulated nonlinearity, revealing conditions for their existence and stability depending on nonlinearity strength and lattice depth.

Contribution

It introduces the concept of surface solitons supported by interfaces with spatially-modulated nonlinearity and identifies stability conditions based on system parameters.

Findings

Surface solitons exist at specific nonlinearity and lattice depth conditions.

Stable surface solitons occur within a limited energy flow band.

Nonlinearity minima at linear index maxima are crucial for soliton support.

Abstract

We address the properties of two-dimensional surface solitons supported by the interface of a waveguide array whose nonlinearity is periodically modulated. When the nonlinearity strength reaches its minima at the points where the linear refractive index attains its maxima, we found that nonlinear surface waves exist and can be made stable only within a limited band of input energy flows, and for lattice depths exceeding a lower threshold.