High-Efficiency All-Dielectric Metasurfaces for Broadband Polarization Conversion

We have presented two polarization convertors based on amorphous silicon metasurfaces. Results show that the cross-polarized transmission of the first polarization convertor is over 90% with over 95% polarization conversion efficiency across the 300-nm bandwidth and maintains high-efficiency performance with big incident angles in this bandwidth. To steer cross-polarized light with an angle according to the generalized Snell’s law, we have created another polarization convertor by choosing several resonators with different geometries in one supercell, achieving full 2π phase control, guiding the co-polarized and cross-polarized transmitted light spatially separated efficiently with broadband operation.