Second Harmonic Generation in monolayer WS2 with double resonant Bragg-Cavities

Abstract

Transition metal dichalcogenides (TMDCs) are semiconducting 2D-materials with a direct bandgap in a range of 1.0 to 2.5 eV [1] . They exhibit strong second-order nonlinearity per unit thickness, making them interesting for nonlinear light-conversion devices [2] . Due to their small thickness, an interaction enhancement is paramount for efficient operation [3] . We have previously demonstrated that such enhancement can be acchieved by embedding TMDCs into monolithic resonators [4] if a gentle coating process compliant with the sensitive nature of the monolayer TMDC flakes is utilized.