title: Active dielectric antenna on chip for spatial light modulation.
abstract: Integrated photonic resonators are widely used to manipulate light propagation in an evanescently-coupled waveguide. While the evanescent coupling scheme works well for planar optical systems that are naturally waveguide based, many optical applications are free-space based, such as imaging, display, holographics, metrology and remote sensing. Here we demonstrate an active dielectric antenna as the interface device that allows the large-scale integration capability of silicon photonics to serve the free-space applications. We show a novel perturbation-base diffractive coupling scheme that allows a high-Q planer resonator to directly interact with and manipulate free-space waves. Using a silicon-based photonic crystal cavity whose resonance can be rapidly tuned with a p-i-n junction, a compact spatial light modulator with an extinction ratio of 9.5 dB and a modulation speed of 150 MHz is demonstrated. Method to improve the modulation speed is discussed.
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005, USA.
authors.forename: Ciyuan
authors.initials: C
authors.lastname: Qiu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Chen
authors.forename: Yang
authors.initials: Y
authors.lastname: Xia
authors.forename: Qianfan
authors.initials: Q
authors.lastname: Xu