Temperature Dependence of Quantum Dots-in-well Infrared Photodetectors (QDIPs) using Photoluminescence

Abstract

Astudy of quantum dots-in-well infrared photodetectors (QDIPs) yields results useful for the creation of a two-colour QDIP. Quantum dot infrared photodetectors (QDIPs) have been shown to be a key technology in mid and long wavelength infrared detection due to their potential for normalincidence operation and low dark current. This study investigates infrared detectors based on intersubband transitions in a novel InAs/In0.15 Ga0.85 As/GaAs quantum dots-in-well (DWELL) heterostructure. In the DWELL structure, the InAsquantum dots are placed in an In0.15 Ga0.85 As well, which in turn is placed in GaAs quantum well with In0.1Ga0.9As barrier. The optical properties of the sample have been studied by the means of photoluminescence using fourier transform infrared spectroscopy. Spectrally tuneable response with bias and long wave IR response at 6.2μm and 7.5μm has been observed.