Influence of the quantum dot shape on the determination of the electronic structure and electron decoherence

Theoretical calculations of electron-phonon scattering rates in AlGaN/GaN quantum dots (QDs) have been performed by means of effective mass approximation in the frame of finite element method. The influence of a symmetry breaking of the carrier's wave function on the electron dephasing time is investigated for various QDs shapes. In a QD system the electron energy increases when the QD shape changes from a spherical to a non-spherical form. In addition, the influence of the QD shape upon the electronic structure can be modulated by external magnetic fields. We also show that the electron-acoustic phonon scattering rates strongly depend upon both the QD shape and the applied magnetic field. As an additional parameter, the QD shape can be used to modify the electron-acoustic phonon interaction in a wide range. Moreover, the scattering rate of different transitions, such as Δm=0(1), presents distinct magnetic field dependency.