Significance of the first excited state position in quantum well infrared photodetectors

Exceptionally rapid progress has been made during the last few years in the performance of GaAs/AlGaAs based quantum well infrared photodetectors (QWI Ps), starting from bound-to-bound which has relatively lower sensitivity, a nd culminating in high performance bound-to-quasibound QWIPs. In this artic le, we discuss and compare the dependence of absorption, responsivity, dark current, and detectivity of QWIPs with the position of the first excited s tate in the quantum well. (C) 1999 Elsevier Science Ltd. All rights reserve d.