Spatial-Spectral Vortex Solitons in Quadratic Lattices

TL;DR

This paper predicts and analyzes stable spatial-spectral vortex solitons in quadratic nonlinear waveguide arrays, revealing their formation through phase gradients and frequency conversion, with broad stability regions.

Contribution

It introduces the concept of spatial-spectral vortex solitons in quadratic lattices and demonstrates their stability through linear analysis.

Findings

Vortex solitons form closed energy loops via phase gradients and frequency conversion.

These vortex modes are stable over a broad parameter range.

The study advances understanding of nonlinear wave phenomena in quadratic lattices.

Abstract

We predict the existence of spatial-spectral vortex solitons in one-dimensional periodic waveguide arrays with quadratic nonlinear response. In such vortices the energy flow forms a closed loop through the simultaneous effects of phase gradients at the fundamental frequency and second-harmonic fields, and the parametric frequency conversion between the spectral components. The linear stability analysis shows that such modes are stable in a broad parameter region.