A silicon nanowire photodetector using Au plasmonic nanoantennas

We suggest a silicon nanowire (SiNW) photodetector side-contacted with hemispherical Au nanoantennas (NAs) that can remarkably amplify the intensity of the near-infrared optical field. The plasmonic NA suppresses visible-range guided mode excitation in SiNW, which enables our photodetector to possess a near-infrared-selective response and overcome the inherent poor optical absorption of Si. The NA can form Schottky contacts with SiNWs for enhancing carrier collection. The vertical NW array also has the geometrically beneficial effects of wide tolerance in light polarization with reduced material consumption.