Room-temperature operating extended short wavelength infrared photodetector based on interband transition of InAsSb/GaSb quantum well**Project supported by the National Natural Science Foundation of China (Grant No. 11574362).

Abstract

Here in this paper, we report a room-temperature operating infrared photodetector based on the interband transition of an InAsSb/GaSb quantum well. The interband transition energy of 5-nm thick InAs0.91Sb0.09 embedded in the GaSb barrier is calculated to be 0.53 eV (), which makes the absorption range of InAsSb cover an entire range from short-wavelength infrared to long-wavelength infrared spectrum. The fabricated photodetector exhibits a narrow response range from to with a peak around at 300 K. The peak responsivity is 0.4 A/W under −500-mV applied bias voltage, corresponding to a peak quantum efficiency of 23.8% in the case without any anti-reflection coating. At 300 K, the photodetector exhibits a dark current density of 6.05×10−3 A/cm2 under −400-mV applied bias voltage and 3.25×10−5 A/cm2 under zero, separately. The peak detectivity is under zero bias voltage at 300 K.