Quantum-Dot Infrared Photodetectors

We present a study of a series of n-i-n InAs quantum-dot infrared photodetectors (QDIPs) with unintentionally doped active regions. Different quantum-dot capping layer materials (GaAs, InGaAs, and AlGaAs) are utilized to tune the operating wavelength and modify the QDIP performance. Normal-incidence operation with high detectivity in the mid (3-5 ) and long (8-12 ) wavelength regimes and the potential for multicolor operation is demonstrated.