Temperature-dependent photoresponsivity and high-temperature (190 K) operation of a quantum dot infrared photodetector

In this letter, a longwave infrared (LWIR) InAs-InGaAs quantum dot infrared photodetector with a peak detection wavelength of 9.9 mu m is reported. A large photoresponsivity of 2.5 A/W and a high peak specific photodetectivity D-* of 1.1x10(8) cm Hz(1/2)/W were obtained at the operating temperature of 190 K. The QDIP showed a strong temperature-dependent photoresponsivity over the temperature range from 78 to 190 K. This effect is shown to be attributable to temperature-dependent electron capture probability. (c) 2007 American Institute of Physics.