The interface optical phonon and electron-phonon interaction in GaN/AlN spherical heterostructures

Based on the dielectric-continuum model, the expression of polarization eigenvector, the dispersion relations, and the electron-phonon interaction Frohlich-like Hamiltonian for interface optical (IO) phonons in multilayer GaN/AlN spherical heterostructures are obtained. As an application of the theory, the dispersion relations and electron-phonon coupling function strengths of the IO phonons are calculated for four-layer GaN/AlN/GaN/AlN spherical heterostructures. The results show that the lower frequency phonons have a much greater contribution to the coupling function Gamma(IO)(i) (r) than higher frequency phonons.