Normal-Incidence-Excited Strong Coupling between Excitons and Symmetry-Protected Quasi-Bound States in the Continuum in Silicon Nitride–WS<sub>2</sub> Heterostructures at Room Temperature
Shun Cao, Hongguang Dong, Jinlong He, Erik Forsberg, Yi Jin, Sailing He
Abstract
monolayer is investigated in detail by both numerical simulations and theoretical calculations. The strong coupling between the q-BIC mode and excitons leads to a remarkable spectral splitting and typical anticrossing behavior of the Rabi splitting, which can be realized in the absorption spectra by varying the grating thickness and asymmetry parameter of the silicon-nitride metasurface, respectively. In addition, both the line width of the q-BIC mode and local electric field enhancement are found to affect the strong coupling, which needs to be considered in detail in q-BIC metasurface designs. This work provides a possible way to enhance light-matter interactions in transition metal dichalcogenides monolayers and pave the way for future quantum and nanophotonic applications.