Responsivity and noise characteristics of AlGaN/GaN-HEMT terahertz detectors at elevated temperatures

Tian Zhi-Feng^{1, 2, 3, 5}, Xu Peng^{1, 4}, Yu Yao^{1, 5}, Sun Jian-Dong^{1, †}, Feng Wei^{1, 6}, Ding Qing-Feng^{1, 2}, Meng Zhan-Wei^{1, 4}, Li Xiang^{1, 6}, Cai Jin-Hua¹, Zheng Zhong-Xin⁷, Li Xin-Xing¹, Jin Lin¹, Qin Hua^{1, 2, 5, ‡}, Sun Yun-Fei⁸

(a) Measured source–drain differential conductance as a function of the gate voltage at different temperatures from 300 K to 473 K. (b) Threshold gate voltage and leakage current at V_G = −5 V. (c) Measured photocurrent as a function of the gate voltage. (d) Normalized self-mixing photocurrent at the optimal gate voltage as a function of the terahertz frequency.