Anomalous increasing super reflectance in chiral matter

TL;DR

This paper explores the unique optical reflection properties of chiral materials described by axion electrodynamics, revealing conditions under which super reflectance occurs and analyzing Kerr effects for potential applications.

Contribution

It demonstrates that chiral media can exhibit anomalous super reflectance and characterizes the Kerr effects, advancing understanding of optical phenomena in Weyl semimetals.

Findings

Super reflectance (R > 1) occurs in certain frequency windows.

Giant Kerr angles are observed within absorption bands.

Kerr ellipticity can determine the sign of magnetic conductivity.

Abstract

Magnetic and anomalous Hall conductivities induce anomalous transport features and novel optical phenomena in chiral systems. Here, we investigate reflection properties on the surface of a medium ruled by axion electrodynamics, which effectively describes optical aspects of Weyl semimetals. We show that these chiral media can manifest anomalous reflectance (R greater than unity) for some frequency windows, depending on the signs of the two involved conductivities. Such a reflectance can increase with the frequency, being always greater than 1 in certain frequency bands. We also examine the complex Kerr angles at normal incidence on the chiral medium. Giant Kerr angle is observed within the absorption window, while the Kerr ellipticity may be used to determine the relative sign of the magnetic conductivity.