Negative refraction and Negative refractive index in an optical uniaxial absorbent medium

TL;DR

This paper demonstrates that negative refraction and negative refractive index can occur in optical uniaxial absorbent media under specific conditions related to the real and imaginary parts of the refractive indices.

Contribution

It reveals the conditions under which negative refraction and negative refractive index occur in absorbent uniaxial media, expanding understanding of optical properties in such materials.

Findings

Negative refraction occurs when the real part of the extraordinary index is less than its imaginary part.

Negative refractive index appears when the incident medium is dense and the incident angle exceeds a critical value.

The study characterizes conditions for negative refraction in absorbent uniaxial media.

Abstract

This work demonstrates the existence of both negative refraction and a negative refractive index in an optical uniaxial absorbent medium that can be characterized by ordinary and extraordinary refractive indices. Negative refraction occurs in any absorbent uniaxial medium if the real part of the extraordinary index is less than its imaginary part. The refractive index is negative when the incident medium is sufficiently dense and the incident angle exceeds a critical angle that is defined here.