| Abstract: | Photonic metasurfaces are metamaterials with reduced dimensionality composed of engineered subwavelength-scale meta-atoms enabling a custom-tailored electromagnetic response of the medium. Besides their extraordinary abilities for molding optical wavefronts with ultrathin planar components, such two-dimensional metastructures are also at the forefront of the challenging physical enigma: What is the effect of surface symmetry properties on light-matter interactions? Recently, we reported on a novel class of metasurfaces – spinoptical metamaterials – which gives rise to a spin-controlled dispersion due to the optical Rashba effect. The observed spin split dispersion arises from the inversion symmetry violation in the metasurface. Spin-symmetry breaking in nanoscale structures caused by spin-orbit interaction, leading to a new branch in optics – spinoptics is presented. The spin-based effects offer an unprecedented ability to control light and its polarization state in nanometer-scale optical devices, thereby facilitating a variety of applications related to nano-photonics. The direct observation of optical spin-Hall effect that appears when a wave carrying spin angular momentum interacts with plasmonic nanostructures is introduced. The optical spin as an additional degree of freedom offers controlled manipulation of spontaneous emission, absorption, scattering, and surface-wave excitation. |
