Qiu, CiyuanChen, JianboXia, YangXu, Qianfan2013-08-222013-08-222012-11-14C. Qiu, J. Chen, Y. Xia and Q. Xu, "Active dielectric antenna on chip for spatial light modulation," <i>Scientific Reports,</i> vol. 2, no. 855, 2012.https://hdl.handle.net/1911/71766Integrated 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.engJournal articlehttp://dx.doi.org/10.1038/srep00855