Chong, KatieStaude, IsabelleJames, AnthonyDominguez, JasonLiu, ShengCampione, SalvatoreSubramania, Ganapathi S.Luk, Ting ShanDecker, ManuelNeshev, DragomirBrener, IgalKivshar, Yuri2016-02-241530-6984http://hdl.handle.net/1885/98390We experimentally demonstrate a functional silicon metadevice at telecom wavelengths that can efficiently control the wavefront of optical beams by imprinting a spatially varying transmittance phase independent of the polarization of the incident beam. Near-unity transmittance efficiency and close to 0-2 phase coverage are enabled by utilizing the localized electric and magnetic Mie-type resonances of low-loss silicon nanoparticles tailored to behave as electromagnetically dual-symmetric scatterers. We apply this concept to realize a metadevice that converts a Gaussian beam into a vortex beam. The required spatial distribution of transmittance phases is achieved by a variation of the lattice spacing as a single geometric control parameter.201510.1021/acs.nanolett.5b017522024-03-03