# Anomalous Nonlinear Optical Effects by Intensity-Dependent Phase-Variation Compensation in Photonic Crystals Containing Hyperbolic Metamaterials

## TL;DR

This paper explores how photonic crystals with hyperbolic metamaterials can produce unusual nonlinear optical effects by adjusting phase variations based on light intensity.

## Contribution

The study introduces a new method to control optical bistability and threshold intensity by designing angle-dependent photonic band edges.

## Key findings

- Angle-independent optical bistability can be achieved with angle-dependent photonic band edges.
- Critical threshold intensity remains constant over a wide range when PBEs are angle-dependent.
- The research offers insights for creating direction-selectable nonlinear optical devices.

## Abstract

We theoretically investigated two types of nonlinear optical effects of photonic band edges (PBEs) in photonic crystals containing hyperbolic metamaterial (HMM) based on the intensity-dependent phase-variation compensation, where the HMM is composed of alternating the noble metal Ag with large-nonlinear-coefficient and dielectric material. Considering nonlinear conditions, the local field strength variation in nonlinear materials with the increase in the incident angle will lead to the movement of the PBE, resulting in two anomalous optical nonlinear effects. When the PBE is angle-independent under the linear condition, the PCs have angle-sensitive optical bistability and the critical threshold intensity always increases. However, if the PBE is designed to have angle dependence under linear conditions, the optical bistability in the PC can be angle-independent, and the critical threshold intensity is angle-independent over a wide range. This research provides important reference values for manufacturing direction-selectable devices that utilize different kinds of nonlinear optical effects.