Abstract
In this work, we analyze and optimize the GaN / AlN coupled quantum well design with and without polarization for achieving intersubband transition wavelength at 1.55 mu m to serve as quantum cascade lasers (QCL) active region. The computations of the electron-LO phonon and electron-photon scattering rates were carried out to optimize the gain media design for intersubband quantum well (QW) lasers. The AlN / GaN coupled QW structure leads to improved design in optimizing the intersubband transition, in comparison to that of single stage GaN / AlN QW structure. The comparison between polar and non-polar coupled QW results in different characteristics in various scattering rates, which in turn leads to different intersubband gain.