Metamorphic InAsSb-based barrier photodetectors for the long wave infrared region

InAs0.6Sb0.4/Al0.75In0.25Sb-based barrier photodetectors were grown metamorphically on compositionally graded Ga1−xInxSb buffer layers and GaSb substrates by molecular beam epitaxy. At the wavelength of 8 μm and T = 150 K, devices with 1-μm thick absorbers demonstrated an external quantum efficiency of 18% under a bias voltage of 0.45 V.