Quasi-bound states in the continuum enhanced wavelength conversion in lossy chalcogenide metasurfaces (Conference Presentation)

We experimentally demonstrate near-infrared to ultraviolet (UV) wavelength conversion in an As2S3-based metasurface that is strongly enhanced by the excitation of a quasi-bound states in the continuum resonance near 1064 nm. We report the all-optical, ultrafast tunability of the QBIC resonance and the third harmonic induced by Kerr effects. These results give rise to a range of novel applications for UV sensors and lasers.