Once fabricated, most nonlinear metasurfaces are locked into a fixed response. We show this doesn’t have to be the case. By placing two metasurfaces face-to-face in a multipass cell, we exploit the Pancharatnam–Berry geometric phase: simply rotating one metasurface relative to the other continuously tunes the phase-matching condition for second-harmonic generation, shifting where the peaks appear across the pump spectrum. For more details, find our paper here
Our work on "Dynamic Control of Phase Matching in Nonlinear Metasurfaces Using Pancharatnam–Berry Phase" is now on Nanophotonics Wiley!
A step toward reconfigurable nonlinear optics.