Affiliation:
1. Institute of Radio Physics and Electronics, University College of Science & Technology, University of Calcutta , 92 A.P.C. Road, Kolkata, West Bengal 700009, India
Abstract
In this paper, mole fraction dependent strain in a III-nitride alloy and its effects on built-in polarization and quantized states in multi-quantum-wells (MQWs) have been investigated. The internal electric field arising out of spontaneous and piezoelectric polarizations in the presence of strain has been calculated. Then, the energy eigenvalues and wavefunctions of carriers in the modified potential well configurations have been computed by solving a time-independent Schrödinger equation using a finite difference method. Next, the overlap integrals between the wavefunctions of bound states in conduction and valence bands, an important consideration for optical transitions, have been computed and plotted. The results are shown taking three nitride-based MQW structures InGaN/GaN, GaN/AlGaN, and InGaN/InAlN as examples. The study helps choose suitable mole fractions for the improved and desired performance of the nitride MQW based devices.