Continuous Wave Second Harmonic Generation Enabled by Quasi-Bound-States in the Continuum on Gallium Phosphide Metasurfaces
Continuous Wave Second Harmonic Generation Enabled by Quasi-Bound-States in the Continuum on Gallium Phosphide Metasurfaces
Resonant metasurfaces are an attractive platform for enhancing the nonlinear optical processes, such as second harmonic generation (SHG), since they can generate large local electromagnetic fields while relaxing the phase-matching requirements. Here, we demonstrate visible range, continuous wave (CW) SHG by combining the attractive material properties of gallium phosphide with …