%0 Journal Article %J Science %D 2017 %T Arbitrary spin-to-orbital angular momentum conversion of light %A Robert C. Devlin %A Ambrosio, Antonio %A Noah A. Rubin %A J. P. Balthasar Mueller %A Capasso, Federico %X
Optical elements that convert the spin angular momentum (SAM) of light into vortex beams have found applications in classical and quantum optics. These elements—SAM-to– orbital angular momentum (OAM) converters—are based on the geometric phase and only permit the conversion of left- and right-circular polarizations (spin states) into states with opposite OAM. We present a method for converting arbitrary SAM states into total angular momentum states characterized by a superposition of independent OAM. We designed a metasurface that converts left- and right-circular polarizations into states with independent values of OAM and designed another device that performs this operation
for elliptically polarized states. These results illustrate a general material-mediated connection between SAM and OAM of light and may find applications in producing complex structured light and in optical communication.