All-optical switching and multistability in photonic structures with liquid crystal defects

TL;DR

This paper demonstrates that one-dimensional photonic crystals with liquid crystal defects can function as all-optical switches exhibiting multistability, due to nonlinear light-matter interactions that modulate the optical Fréedericksz transition.

Contribution

It introduces a novel all-optical switching mechanism in photonic structures with liquid crystal defects based on nonlinear coupling, distinct from static electric field effects.

Findings

Demonstration of all-optical switching in liquid crystal photonic structures

Observation of light-induced multistability due to nonlinear effects

Spectral modulation of the Fréedericksz transition threshold

Abstract

We demonstrate that one-dimensional photonic crystals with pure nematic liquid-crystal defects can operate as all-optical switching devices based on optical orientational nonlinearities of liquid crystals. We show that such a periodic structure is responsible for a modulated threshold of the optical Fr\'eedericksz transition in the spectral domain, and this leads to all-optical switching and light-induced multistability. This effect has no quasi-statics electric field analogue, and it results from nonlinear coupling between light and a defect mode.