Realization of circularly polarized beam based on plasmonic metasurface

摘要

We present a quarter-wave plate composed of two pairs of cross-shaped elliptical nanoatennas. This setup can transform linearly polarized incident light to circular polarized light at a wavelength of 862nm. The cross-shaped elliptical configuration can control the amplitude and phase of incident light. By the modulation of the elliptical size, equal amplitude and specific phase difference can be obtained in orthogonal directions. Furthermore, as a quarter-wave plate, this configuration is not sensitive to the polarized direction of the linearly polarized incident beam. In order to verify the designed metasurface, numerical simulation were performed using the finite difference time domain method. Our results may benefit novel photonics devices design such as polarization manipulation, optical sensing, optical detecting, and photonic integration.