Ga2O3‑Based Solar-Blind Position-Sensitive Detector for Noncontact Measurement and Optoelectronic Demodulation

• Published in: Nano letters 2022-06, Vol.22 (12), p.4888-4896
• Main Authors: Chen, Yancheng, Yang, Xun, Zhang, Chongyang, He, Gaohang, Chen, Xuexia, Qiao, Qian, Zang, Jinhao, Dou, Wenjie, Sun, Pengxiang, Deng, Yuan, Dong, Lin, Shan, Chong-Xin
• Format: Article
• Language: English
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.2c01322

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.