Period-doubled Floquet Solitons

TL;DR

This paper introduces and experimentally demonstrates Floquet solitons with double the period of the drive in a photonic topological insulator, revealing new nonlinear phenomena in topological photonics.

Contribution

It presents the first experimental realization of period-doubled Floquet solitons in a topological photonic system, combining topology, nonlinearity, and periodic driving.

Findings

Demonstration of period-doubled Floquet solitons in a photonic lattice

Observation of nonlinear self-focusing leading to spatial solitons

Platform for exploring interplay of topology, nonlinearity, and periodic driving

Abstract

We propose and experimentally demonstrate a family of Floquet solitons in the bulk of a photonic topological insulator that have double the period of the drive. Our experimental system consists of a periodically-modulated honeycomb lattice of optical waveguides fabricated by femtosecond laser writing. We employ a Kerr nonlinearity in which self-focusing gives rise to spatial lattice solitons. Our photonic system constitutes a powerful platform where the interplay of time-periodic driving, topology and nonlinearity can be probed in a highly tunable way.