First-principles study of high-field-related electronic behavior of group-III nitrides

Based on accurate band structures of AlN, GaN, and InN, we report physical quantities related to high-field electron transport, including effective masses, energies of inflection points, and satellite valleys in the conduction band. The band structures are obtained from density functional theory with a hybrid functional, as well as many-body perturbation theory based on the G₀W₀ approach. We also calculate the electron-energy relaxation time due to the electron-longitudinal-optical-phonon interaction within the Fr\"ohlich model. Our results provide insights into the physical origin of negative differential resistance and the high-frequency characteristics of group-III nitrides and their alloys under high-field operation.