Integration of 2D Materials in Tunable Open Microcavities for Strong Light-Matter Coupling

Abstract

Polaritons—hybrid quasiparticles arising from the strong coupling between excitons and photons—have been proposed as a potential route to achieving high-temperature superconductivity via Bose-Fermi interactions. Transition metal dichalcogenides (TMDCs), particularly MoS2, offer a promising platform for exploring these effects due to the existence of indirect excitons with sufficient oscillator strength. In particular, control over the oscillator strength of excitons is crucial for engineering polariton interactions. In Chapter 2, we first design and demonstrate a tunable open microcavity that enables the formation of exciton-polaritons in monolayer WS2. We illustrate the tunability of cavity and confirm strong coupling of excitons and photons through characteristic anti-crossing behavior as the resonances are tuned across each other. In Chapter 3, we extend our study to bilayer MoS2, investigating the effects of charge doping and applied in-plane electric fields on its optical response. Our results reveal significant modifications to the excitonic linewidths, energy shifts, and oscillator strengths. We also observe a spatially varying response under in-plane fields, indicating towards charge redistribution and polaron effects.