Active deflection angle switching via the phase change of GeiSbiTes nanorod metasurface

We propose a novel method for active switching of optical deflection angle via the phase change of GeiSbiTes (GST) metasurface. The metasurface is composed of GST nanorods whose geometries are designed by means of Pancharatnam-Berry phase and propagation phase to switch transmission directivity via the phase change. As a result, assuming normal incidence of circularly polarized light at the wavelength of 1650 nm, we achieved deflection angle switching of transmitted light with cross-polarization from −24.4° to +24.4° according to change of GST phase from the amorphous to the crystalline phase.