Cubic GaN/AlGaN based quantum wells optimized for applications to tunable mid-infrared photodetectors

Abstract

We propose a method which delivers optimal cubic GaN/AlGaN quantum well profiles such that both the Stark effect and peak intersubband absorption from the ground to the first excited electronic state, in a prescribed range of bias electric fields, are maximized. Our method relies on the Genetic Algorithm which finds globally optimal structures with a predefined number of embedded layers. We investigate simple rectangular quantum wells with embedded step layers for applications in tunable mid-infrared photodetectors. The effects of band nonparabolicity are taken into account to refine our model.