Chiral Discrimination in Helicity-Preserving Fabry-P\'erot Cavities

TL;DR

This paper demonstrates that helicity-preserving Fabry-Pérot cavities can significantly enhance the circular dichroism of chiral molecules, enabling the observation of chiral cavity polaritons and potential applications in ultrasensitive chiral sensing.

Contribution

It introduces a novel cavity design that enhances chiroptical responses and reports the first observation of chiral cavity polaritons in the strong coupling regime.

Findings

Chiroptical response increased by 100 times

First observation of chiral cavity polaritons

Cavity design enables efficient coupling of chiral molecules

Abstract

We theoretically study circular dichroism of chiral molecules embedded inside a helicity-preserving Fabry-P\'erot cavity. We find an increase of the intrinsic chiroptical response of the molecules by 2 orders of magnitude and report the first clear signature of chiral cavity polaritons upon entering the regime of strong light-matter coupling. We study a cavity design based on two dielectric photonic crystal mirrors acting, in a narrow frequency range, as efficient polarization cross-converters in transmission for one polarization and almost perfect reflectors for the other polarization. We show that a Pasteur medium hosted inside such a cavity can couple efficiently to both the outside of the cavity and to the helicity-preserving mode, inheriting an enhanced chiral character. We expect such a device to be useful in the future to design ultrasensitive chiral sensors for optics and stereochemistry.