Design and Analysis of Multicolor QDIP Based on Metallic Nanoslits Array

In this letter, we propose a new design for a multicolor InAs/GaAs quantum dot (QD) infrared photodetector based on metallic nanoslits array. The proposed device has an absorption coefficient of more than 50% for designed wavelengths in the infrared (IR) range. We analyze the absorption characteristics of the InAs/GaAs QDs affected by metallic nanoslits. Distributed Bragg reflector layers with a buried grating layer are used for enhancement of local field in active layer. The dielectric function of the InAs/GaAs QD layer is calculated by modified Maxwell-Garnett model considering homogeneous and inhomogeneous broadenings, which is then substituted into Maxwell's equations. Results show absorption enhancement of ~100% for certain wavelengths in the IR range, compared with reference structure.