Optical spin-Hall effect as a route for spin-enabled optics

In this talk, we will explore opportunities of spin-induced manipulation of light with metamaterials by exploiting the optical spin-Hall effect. The interaction between spin and motion using geometric phase provides us an interesting way to manipulate the orbital motion of light, in addition to the driving force from a refractive-index gradient. As one example, light carries both orbital and spin angular momenta. By constructing metasurfaces with plasmonic atoms in modifying geometric phase locally, splitting of the angular orbital of light can be induced by flipping the spin of incident light towards the metasurface. As another example, a metasurface can act as a holographic interface between an incident plane wave and the surface-plasmon-polariton (SPP) on an optical chip. Geometric phase elements on the metasurface allow us to gain spin-splitting and arbitrary control of the shapes and phases of the local SPP orbitals. A linearly polarized incident light with rotating polarization angle can be used to play a motion picture of orbital motion using SPP. As a final example, we will explore how metamaterials can be utilized to generate pseudo magnetic field for light to allow direct demonstration of optical spin Hall effect using such a pseudo magnetic field. These investigations provide a feasible route to a wide variety of applications, including spin-enabled imaging, data storage and integrated optical components.