Synthesis and photonic applications of gallium nitride nanowires

High quality single crystal gallium nitride nanowires (GaN NWs) are synthesized with a novel chemical vapor deposition (CVD) method. Transport studies of single crystal GaN nanowire devices exhibit n-type transistor behavior with high electron mobility. Ultraviolet (UV) light sensors are fabricated with GaN NW devices. The nanowire sensors exhibited a substantial increase in conductance upon UV light exposure. In addition to the selectivity to different light wavelengths, short response and recovery time have also been obtained. In addition, a polarization anisotropy effect was demonstrated and studied for GaN NWs working as polarized UV detectors. The nanowire conductance varied periodically with the polarization angle of the incident light (θ), which can be well fitted into a function of cos²θ.