Two-dimensional beam scanner based on silicon optical phased array with half-wavelength period

We demonstrate a 63-channel grating-lobe-free optical phased array, in which end-fire antennas were fabricated with a pitch of 775 nm to eliminate grating lobe. Phase mismatch was configured to suppress the optical crosstalk in the dense waveguides. Two-dimensional beam steering within 16°× 2.7° were presented by thermal phase shifting and wavelength tuning.