Guided Waves in Asymmetric Hyperbolic Slab Waveguides. The TM Mode Case

TL;DR

This paper investigates nonlinear TM guided wave modes in asymmetric hyperbolic slab waveguides, revealing new cutoff frequencies and nonlinear effects, including modes localized in the nonlinear substrate that require threshold power for excitation.

Contribution

It introduces the dispersion relations for TM modes in asymmetric hyperbolic waveguides and explores the impact of nonlinearity, including the existence of unique localized modes absent in linear waveguides.

Findings

Additional cutoff frequencies for TM modes are identified.

Nonlinear effects alter dispersion relations significantly.

Localized modes in the nonlinear substrate require threshold power for excitation.

Abstract

Nonlinear guided wave modes in an asymmetric slab waveguide formed by an isotropic dielectric layer placed on a linear or nonlinear substrate and covered by a hyperbolic material are investigated. Optical axis is normal to the slab plane. The dispersion relations for TM waves are found. It is shown that there are additional cut-off frequencies for each TM mode. The effects of the nonlinearity on the dispersion relations are investigated and discussed. There are the modes, which are corresponded with situation where the peak of electric field is localized in the nonlinear substrate. These modes are absent in the linear waveguide. To excite these modes the power must exceed certain threshold value.