Reverse Circular Bragg Phenomenon

TL;DR

This paper provides an exact electromagnetic analysis of circularly polarized light in chiral media, revealing a reverse Bragg resonance in negative refraction regimes and conditions for optical activity to offset structural chirality.

Contribution

It introduces a full electromagnetic solution for axial propagation in chiral media and uncovers reverse Bragg phenomena and birefringence conditions.

Findings

Reverse circular Bragg resonance occurs in negative refraction regimes.

Symmetries of the characteristic matrix reveal new insights.

Optical activity can offset structural chirality, leading to birefringence.

Abstract

The axial propagation of circularly polarized light in an optically active structurally chiral medium is exactly solved via full electromagnetic analysis. Some symmetries of the system's characteristic matrix reveal new insights, which are confirmed by coupled wave theory. For extreme values of chirality, now accessible via metamaterials, a reverse circular Bragg resonance arises in the negative refraction regime where handedness reversal of counterpart modes occurs. A condition is identified under which optical activity offsets structural chirality, rendering the medium simply birefringent.