Quantum-dot photodetector operating at room temperatures: diffusion-limited capture

Abstract

Recent investigations have shown very promising characteristics of quantum-dot far-infrared photodetectors at 150–300 K. We propose a device model for the quantum-dot photodetector operating at high temperatures, where the electron mean free path due to electron–phonon scattering is small. In this temperature range, the electron energy relaxation in a quantum dot is very fast, so that the photoelectron capture is determined by electron diffusion in the field of potential barriers surrounding the charged quantum dots. The model with diffusion-limited capture is used to evaluate the photodetector performance.