High detectivity InAs quantum dot infrared photodetectors

We report a high detectivity of 3x10(11) cm Hz(1/2)/W at 78 K for normal-incidence quantum dot infrared photodetectors with ten layers of undoped InAs/InGaAs/GaAs quantum dot active regions. The high detectivity seen at 1.4 V corresponds to photoresponse peaks at 9.3 and 8.7 mum for positive and negative bias, respectively. (C) 2004 American Institute of Physics.