Ga<sub>2</sub>O<sub>3</sub>-Based Solar-Blind Position-Sensitive Detector for Noncontact Measurement and Optoelectronic Demodulation
Yancheng Chen, Xun Yang, Chongyang Zhang, Gaohang He, Xuexia Chen, Qian Qiao, Jinhao Zang, Wenjie Dou, Pengxiang Sun, Yuan Deng, Lin Dong, Chongxin Shan
Abstract
As a kind of photodetector, position-sensitive-detectors (PSDs) have been widely used in noncontact photoelectric positioning and measurement. However, fabrications and applications of solar-blind PSDs remain yet to be harnessed. Herein, we demonstrate a solar-blind PSD developed from a graphene/Ga2O3 Schottky junction with a 25-nanometer-thick Ga2O3 film, in which the absorption of the nanometer-thick Ga2O3 is enhanced by multibeam interference. The graphene/Ga2O3 junction exhibits a responsivity of 48.5 mA/W and a rise/decay time of 0.8/99.8 μs at zero bias. Moreover, the position of the solar-blind spot can be determined by the output signals of the PSD. Using the device as a sensor of noncontact test systems, we demonstrate its application in measurement of angular, displacement, and light trajectory. In addition, the position-sensitive outputs have been used to demodulate optical signals into electrical signals. The results may prospect the application of solar-blind PSDs in measurement, tracking, communication, and so on.