Voltage-tuning in multi-color quantum well infrared photodetector stacks

Abstract

A systematic study of stacked quantum well infrared photodetectors is undertaken to improve the understanding of the voltage-tunable multi-color spectral response. The multi-color capability is achieved by sequentially growing conventional one color detectors, separated by conducting layers. The behavior of the stacked devices is proven to correspond to the individual detectors simply acting in series with each other. The dc resistance, photocurrent and dynamic resistance characteristics of the individual detectors are examined and correlated with the voltage-tuning in the stack.