title: On-chip silicon optical phased array for two-dimensional beam steering.
abstract: A 16-element optical phased array integrated on chip is presented for achieving two-dimensional (2D) optical beam steering. The device is fabricated on the silicon-on-insulator platform with a 250 nm silicon device layer. Steering is achieved via a combination of wavelength tuning and thermo-optic phase shifting with a switching power of P(π)=20  mW per channel. Using a silicon waveguide grating with a polycrystalline silicon overlay enables narrow far field beam widths while mitigating the precise etching needed for conventional shallow etch gratings. Using this system, 2D steering across a 20°×15° field of view is achieved with a sidelobe level better than 10 dB and with beam widths of 1.2°×0.5°.
authors.forename: David
authors.initials: D
authors.lastname: Kwong
authors.forename: Amir
authors.initials: A
authors.lastname: Hosseini
authors.forename: John
authors.initials: J
authors.lastname: Covey
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiaochuan
authors.initials: X
authors.lastname: Xu
authors.forename: Harish
authors.initials: H
authors.lastname: Subbaraman
authors.forename: Ray T
authors.initials: RT
authors.lastname: Chen