Low-bias, high-temperature operation of an InAs-InGaAs quantum-dot infrared photodetector with peak-detection wavelength of 11.7 mu m

We report on a low-bias InAs-InGaAs quantum-dot (QD) infrared photodetector (QDIP) with operating temperature of 150 K. Longwave-infrared (LWIR) detection at the peak wavelength of 11.7 mu m was achieved. Peak specific photodetectivity D-center dot of 1.7 x 10(9) and 9.0 x 10(7) cm Hz (1/2)/W were obtained at the operating temperature T of 78 K and 150 K, respectively. A large photoresponsivity of 8.3 A/W and high photoconductive gain of 1100 were demonstrated at a low-bias voltage of V = 0.5 V at T = 150 K. The low-bias and high-temperature performance demonstration based on InAs-GaAs material systems indicates that the QDIP technology is promising for LWIR sensing and imaging. (C) 2008 Elsevier B.V. All rights reserved.