Proof of enantioselectivity in a multilayer with a strong exciton polariton coupling and through asymmetric polarization

TL;DR

This study demonstrates enantioselectivity in a multilayer plasmonic system through strong exciton-polariton coupling and asymmetric polarization, enabling polarization-dependent spectral contrast for chiral molecules.

Contribution

It introduces a novel plasmonic multilayer setup that achieves enantioselectivity via exciton-polariton interactions combined with asymmetric polarization effects.

Findings

Enantioselective spectral contrast observed for D and L penicillamine.

Strong exciton-polariton coupling enhances optical forces on enantiomers.

Asymmetry in polarization leads to distinct optical flux for different enantiomers.

Abstract

The plasmonic investigation involves activating a multilayer consisting of silver, platinum, silica, and silicon. Hybrid waveguide and surface plasmon polariton modes define the device plasmonic activity. The presence of micrometric features on the multilayer surface facilitates the formation of the waveguide mode. Moreover, they produce a transmitted signal that is associated with localized surface plasmon resonance. A red dye adsorbed onto a multilayer surface causes a strong coupling between excitons and polaritons. This coupling increases the radiation force, and the dye-induced enhancement of radiation force supports the use of passive chirality spectroscopy to measure the optical forces acting on enantiomers. In conclusion, when a Kretschmann scheme is combined with the de-polarization, a built-in asymmetry results in a different optical flux of spectrum photons, resulting in distinct, enantioselective, and solely polarization-dependent spectral contrast, and the enantioselectivity is demonstrated for the D and L penicillamine.