Towards Double Resonant Cavity Enhanced Second Harmonic Generation in Monolayer MoS₂

A characteristic property of monolayered transition metal dichalcogenides is their strong nonlinear response. While they display a high conversion efficiency per atomic layer, due to their low thickness, the absolute value of their nonlinear response remains low. Here enhancement of the second harmonic generation (SHG) of monolayer MoS2 through the design, fabrication, and characterization of a monolithic microcavity, which aims to be double resonant at a fundamental wavelength of lambda = 800 nm as well as its second harmonic, is demonstrated. The MoS2 monolayers are embedded in such a cavity, with the aim to simultaneously enhance the light-matter interaction at the excitation wavelength and the SHG from the monolayers. A resonance enhancement for the SHG process is achieved through the cavity.