Optical phased array based on subwavelength grating antennas

We demonstrated a large aperture 1×16 silicon photonics OPA leveraging one-millimeter-long subwavelength grating antennas (SGA). The SGA is implemented by placing subwavelength silicon segments in the vicinity of the conventional strip waveguide so that they only interact with the evanescent field of the strip waveguide. The strength of the SGA can be conveniently controlled by tuning the location and size of the silicon segments. With the 1×16 OPA, a light beam of 0.1°×1.8° with a sidelobe suppression ratio > 10 dB is achieved.