Multiplexing-oriented plasmon-MoS2 hybrid metasurfaces driven by nonlinear quasi bound states in the continuum

Abstract

The nonlinear optical devices with wavelength-multiplexed high-nonlinear susceptibilities may have many potential applications in frequency metrology 1 , timing characterization 2 , quantum information 3 , when multiple color signals need to be nonlinearly processed simultaneously. It is possible to realize this kind of device with metasurfaces using their various nanostructure designability.Here we introduce the nonlinear plasmon-assisted MoS2 hybrid metasurfaces with multiple high-Q radiation channels that originate from the bound states in the continuum. By exploiting the sharp resonances of light-trapping modes, we demonstrate that the optical nonlinearity can be significantly boosted and smartly tuned. The mechanisms to identify and create the trapped resonances that fueled by the bound states in the continuum are elaborated, and our work suggests a route to use nonlinear hybrid metasurfaces for realizing high-efficiency multi-channel second-order nonlinear optical devices.