Circular dichroism induction in WS 2 by a chiral plasmonic metasurface

Abstract

We investigate the interaction between a monolayer of WS 2 and a chiral plasmonic metasurface. WS 2 possesses valley excitons that selectively couple with one-handed circularly polarized light. At the same time, the chiral plasmonic metasurface exhibits spin-momentum locking, leading to a robust polarization response in the far field. Using a scattering formalism based on the coupled mode method, we analyze various optical properties of the WS 2 monolayer. Specifically, we demonstrate the generation of circular dichroism in the transition metal dichalcogenide (TMD) by harnessing the excitation of surface plasmon polaritons (SPPs) in the metasurface. Moreover, we observe the emergence of other guided modes, opening up exciting possibilities for further exploration in TMD-based devices.