Optical Nonlinearities in All-Dielectric Metasurfaces

Subwavelength all-dielectric metasurfaces are well-known to support strongly localized Mie-type modes. In this work we show our results on nonlinear optical frequency mixing enhanced by magnetic and electric dipole modes in GaAs metasurfaces. By pumping the semiconductor metasurface with two 45-fs laser pulses, we were able to generate eleven new frequencies simultaneously. Moreover, we experimentally demonstrate that the improvement of the conversion efficiency of the nonlinear processes can be achieved by utilizing out-of-plane Mie resonances in the metasurface using broken-symmetry design nanoresonators.