We propose a near half-wavelength one-dimensional (1-D) optical phased array (OPA) antenna based on a superlattice structure design approach which overcomes conventional crosstalk problems and offers high resolution broadband beam steering while preserving a small footprint size. The performance of the OPA have been optimized by investigating the parameters of the strip gratings, including grating depth, grating period and number of antennas. Results show that the proposed OPA can steer 130° in the longitudinal axis with a divergence beam width of 2.52° at the main lobe for 33 grating elements. This provides 52 resolution points which achieves a 44% improvement over recent 1-D superlattice gratings array antenna system.
A fiber-chip spot size converting edge coupler has been presented on silicon-on-insulator (SOI) platform. The design is optimized for the wavelength of 1.55 μm using a fully-vectorial three-dimensional eigenmode expansion method. The proposed coupler combines an inverse taper edge coupler and a mode expander on a 220-nm-thick SOI platform. Results show that our proposed coupler could achieve an output profile of 10.4 μm×220 nm and 90% coupling efficiency operating for both transverse-electric and transverse-magnetic polarizations.