Analysis of the Photocurrent in Quantum Dot Infrared Photodetectors

Abstract
We calculate the photocurrent in realistic quantum dot infrared photodetectors (QDIPs) using a developed device model. This model takes into account the space charge and the self-consistent electric potential in the QDIP active region, the activation character of the electron capture and its limitation by the Pauli principle, the thermionic electron emission from QDs and thermionic injection of electrons from the emitter contact into the QDIP active region, and the existence of the punctures between QDs. The developed model yields the photocurrent in a QDIP as a function of its structural parameters, applied voltage, and intensity. The calculated dependences are in agreement with available experimental data. The obtained results point the way for the optimization of QDIPs in order to realize their potential advantages.