Md. Kim et al., Normal incidence infrared photoconductor of self-assembled InAs quantum dots in modulation doped AlGaAs/GaAs heterostructures, J CRYST GR, 227, 2001, pp. 1162-1165
We have designed and fabricated a quantum dot infrared photodetector which
utilizes the lateral transport of photoexcited carriers in the A1GaAs/GaAs
two-dimensional (2D) channels. A photocurrent signal has been observed in t
he range of 9.5-11 mum with a peak at 10.5 mum due to the buund-to-continuu
m intersubband absorption of the normal incidence radiation in the self-ass
embled InAs quantum dots. The peak detectivity was measured to be 1 x 10(9)
om Hz(1/2)/W at 220K. The high detectivity is realized mainly by low dark
current, high mobility and a long lifetime of photoexcited carriers in the
modulation doped 2D channels. (C) 2001 Published by Elsevier Science B.V.