Voltage-tunable, multicolor infrared detectors

摘要

A tunable radiation detector comprises a superlattice structure having a plurality of quantum well units each separated by a first potential barrier and each having at least two doped quantum wells separated by a second potential barrier. The wells each have a lower energy level and a higher energy level. The first potential barriers substantially impede electrons at the lower levels from tunneling therethrough. The second potential barriers permit electrons at the lower levels to tunnel therethrough and prevent energy-level coupling between adjacent ones of the doped quantum wells. A biasing circuit is connected across the semiconductor superlattice structure. A photocurrent sensor is provided for measuring the amount of radiation absorbed by the semiconductor superlattice structure. The superlattice structure is made a part of a hot-electron transistor for providing amplification.