Publications Details

Highly Efficient Solar-Blind Single Photon Detectors

Armstrong, Andrew A.; Klein, Brianna A.; Allerman, A.A.; Baca, A.G.; Crawford, Mary H.; Pickrell, Gregory P.; Perez, Carlos P.; Podkaminer, Jacob; Siegal, Michael P.; Jayawardena, Asanka; Ahyi, Ayayi; Dhar, Sarit

Photodetectors sensitive to the ultra-violet spectrum were demonstrated using an AlGaN high electron mobility transistor with an GaN nanodot optical floating gate. Peak responsivity of 2 x 10⁹ A/W was achieved with a gain-bandwidth product > 1 GHz at a cut-on energy of 4.10 eV. Similar devices exhibited visible-blind rejection ratios > 10⁶. The photodetection mechanism for $β$-Ga₂O₃ was also investigated. It was concluded that Schottky barrier lowering by self-trapped holes enables photodetector gain.