Chiral Optical Tamm States at the Interface between a Cholesteric and an All-Dielectric Polarization-Preserving Anisotropic Mirror

TL;DR

This paper introduces chiral optical Tamm states at the interface of a cholesteric liquid crystal and a dielectric mirror, highlighting their high Q factor and potential for laser and sensing applications.

Contribution

It demonstrates the use of a metal-free, all-dielectric polarization-preserving mirror to control chiral optical Tamm states with high Q factors.

Findings

High Q factor achieved with all-dielectric structure

Field localization near the interface with exponential decay

Field penetration blocked at specific wavelengths

Abstract

The chiral optical Tamm state is a new localized state of light at the interface between a polarization-preserving anisotropic mirror and an optically chiral medium such as a cholesteric liquid crystal. In this study the metal-free polarization-preserving mirror is used for efficient resonance control. We stress the advantage of the all-dielectric structure in obtaining high Q factor. The light is localized near the interface and the field decreases exponentially with the distance from the interface. The penetration of the field into the chiral medium is virtually blocked at wavelengths corresponding to the photonic band gap and close to the pitch of the helix. The polarization-preserving mirror has another photonic band gap as well. Our analytics agrees well with precise calculations, enabling intelligent design for laser and sensing applications.