Demonstration of infrared nBn photodetectors based on the AlInAsSb digital alloy materials system

We report an nBn photodetector based on the AlInAsSb digital alloy materials system, which has advantage of a near-zero valence band offset. These photodetectors have achieved 28% external quantum efficiency, dark current densities 2.6 × 10−3 A/cm2 at 300 K and 1.8 10−9 100 with −0.5 V bias, detectivity 1.7 1010 Jones room temperature under 2 μm wavelength illumination.