A Method To Extend Wavelength Into Middle-Wavelength Infrared Based On Inassb/(Al)Gasb Interband Transition Quantum Well Infrared Photodetector

We present a method to extend the operating wavelength of the interband transition quantum well photodetector from an extended short-wavelength infrared region to a middle-wavelength infrared region. In the modified InAsSb quantum well, GaSb is replaced with AlSb/AlGaSb, the valence band of the barrier material is lowered, the first restricted energy level is higher than the valence band of the barrier material, the energy band structure forms type-II structure. The photocurrent spectrum manifest that the fabricated photodetector exhibits a response range from 1.9 mu m to 3.2 mu m with two peaks at 2.18 mu m and 3.03 mu m at 78K.