Optical bistability with bound states in the continuum in dielectric gratings

TL;DR

This paper investigates optical bistability in dielectric gratings with bound states in the continuum, demonstrating how Kerr nonlinearity induces bistability near these states through theoretical modeling and numerical validation.

Contribution

It introduces a theoretical framework modeling optical bistability as a nonlinear oscillator driven by a single field, supported by numerical simulations.

Findings

Optical bistability occurs near bound states in the continuum due to Kerr nonlinearity.

Theoretical model successfully predicts bistability onset.

Numerical simulations confirm the theoretical predictions.

Abstract

We consider light scattering by dielectric gratings supporting optical bound states in the continuum. Due to the presence of instantaneous Kerr nonlinearity the critical field enhancement in the spectral vicinity of the bound state triggers the effect of optical bistability. The onset of bistability is explained theoretically in the framework of the temporal coupled mode theory. As the central result we cast the problem into the form of a singly field-driven nonlinear oscillator. The theoretical results are verified in comparison against full-wave numerical simulations.