Avalanche multiplication due to impact ionization in quantum-well infrared photodetectors: A quantitative approach

Abstract

We investigate the influence of avalanche multiplication by impact ionization on the photoconductive gain and the noise gain in quantum-well infrared photodetectors (QWIPs). A quantitative method is presented allowing the avalanche multiplication factor M and its field dependence to be determined from the measured photoconductive gain and noise gain. The approach is demonstrated using an In0.30Ga0.70As/GaAs QWIP.