Optical travelling-wave antenna for circularly polarized broadside emission

Abstract

The technology described herein is generally directed towards an optical grating antenna designed as a travelling wave or leaky wave antenna, based on laterally asymmetrical and rotated structural perturbations along the antenna. In one implementation, the perturbations are protrusions in the form of nanopillar pairs distributed along the top (wire) of the antenna. The lateral asymmetry and opposite rotations of each pairs'perturbations, relative to each other and to the wire in the segment pairs'distribution, produces strong emissions with rotated polarity in the broadside direction, unlike conventional grating antennas that have a stopband at broadside emission. The optical antenna, which can be implemented as a silicon-on-insulator waveguide, is suitable for rotated polarity in emissions from the antenna, which can be tunable polarization based on rotation-related design parameters. Instead of nanopillar pairs, other implementations can have structural perturbations of different geometries, including different shapes and/or cavities in the antenna structure.

Dependencies are inferred from the claim text.