Photodetection of Infrared Photodetector Based on Surrounding Barriers Formed by Charged Quantum Dots

The photodetection performance of the quantum dot infrared photodetector (QDIP) is always a hot topic. In this paper, a model is proposed for the photocurrent of the QDIP, which not only considers the influence of the potential barrier around quantum dot on the photoconductive gain but includes the contribution of the quantum efficiency as well, based on the current balance relationship under dark conditions. The corresponding calculated results show a good agreement with the measured data, and they are furthermore used to calculate the responsivity, which can provide the device designers with the theoretical guidance for the optimization of the detector and the improvement of the device performance.