Quantum dot long-wavelength detectors
Long-wavelength infrared detectors operating at elevated temperatures are critical for imaging applications. InAs/GaAs quantum dots are an important material for the design and fabrication of high-temperature infrared photodetectors. Quantum dot infrared photodetectors allow normal-incidence operation, in addition to low dark currents and multispectral response. The long intersubband relaxation time of electrons in quantum dots improves the responsivity of the detectors, contributing to better high-temperature performance. We have obtained extremely low dark currents (Idark = 1.7 pA, T = 100 K, Vbias = 0.1 V), high detectivities (D* = 2.9×108 cmHz1/2/W, T = 100 K, Vbias = 0.2 V), and high operating temperatures (T = 150 K) for these quantum-dot detectors. These results, as well as infrared imaging with QDIPs, will be described and discussed.