Mechanisms of intersubband transition in n-type III-V quantum well superlattice and improvement on absorption for TE polarized field

摘要

In this paper, the theoretical study of intersubband transitioons in quantum well infrared photodetectros (QWIPs) applying the eight bands k.p model incorporated with envelope function approximation is described. The fous of the work is on the intersubband transition in n-type II-V QWIP based on AlGaAs/GaAs and AlGaAs/InGaAs material system, with particular emphasis placed on the physics of TE excited transition and the improvement of resulted absorption. Various theoretical absorption spectra of the two material systems are compared, the distinct mechanisms of the intersubband transition for the two material systems are proposed. Possible ways of improving on the absorption for such excitation are also investigated and discussed.