Resonant tunneling quantum dot infrared photodetector (RT-QDIP): Separating dark current and photocurrent

The reduction of dark current in quantum dot (QD) infrared photodetectors (QDIP), which uses resonant tunneling (RT) barriers to selectively block dark current while transmitting photocurrent, was investigated. A heterostructure design for such a RT-QDIP comprising ten InAs/GaAs QD layers was used for investigation. An RT-QDIP and a conventional QDIP were grown and fabricated to compare the dark current in both devices. It was observed that the reduction in dark current due to the RT design is approximately 10 2 and is the lowest measured dark current in a QDIP at these temperatures. The results show that the new QDIP design should provide a significant improvement in QDIP performance by reducing dark current for high-temperature operation.