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

Abstract

In this letter, a longwave infrared (LWIR) InAs–InGaAs quantum dot infrared photodetector with a peak detection wavelength of 9.9μm is reported. A large photoresponsivity of 2.5A∕W and a high peak specific photodetectivity D* of 1.1×108cmHz1∕2∕W were obtained at the operating temperature of 190K. The QDIP showed a strong temperature-dependent photoresponsivity over the temperature range from 78to190K. This effect is shown to be attributable to temperature-dependent electron capture probability.