Dyakonov-Tamm wave at the planar interface of a chiral sculptured thin film and an isotropic dielectric material

TL;DR

This paper investigates Dyakonov-Tamm surface waves at the interface between an isotropic dielectric and a chiral sculptured thin film, revealing a broader propagation range due to the film's periodic nonhomogeneity.

Contribution

It introduces the concept of Dyakonov-Tamm waves at this specific interface and analyzes how the chiral STF's structure affects wave propagation.

Findings

Broader propagation direction range for Dyakonov-Tamm waves

Smaller refractive index range needed for the isotropic material

Enhanced surface wave existence due to periodic nonhomogeneity

Abstract

Surface waves, named here as Dyakonov-Tamm waves, can exist at the planar interface of an isotropic dielectric material and a chiral sculptured thin film (STF). Due to the periodic nonhomogeneity of a chiral STF, the range of the refractive index of the isotropic material is smaller but the range of the propagation direction in the interface plane is much larger, in comparison to those for the existence of Dyakonov waves at the planar interface of an isotropic dielectric material and a columnar thin film.