Cascaded metasurfaces for complete phase and polarization control

A metasurface lens that focuses light and controls its polarization at a wavelength of 2 mu m is presented. This lens demonstrates high transmission and complete phase control within a subwavelength thickness at near-infrared frequencies. By cascading four patterned sheets, the efficiency is dramatically improved over more common single sheet designs. In addition, by utilizing anisotropic sheets, arbitrary birefringence can be achieved. A planar lens that both focuses light and converts its polarization from linear to circular is analyzed. (C) 2013 AIP Publishing LLC.