Band parameters and strain effects in ZnO and group-III nitrides

We present consistent sets of band parameters (including band gaps, crystal-field splittings, effective masses, Luttinger and E_P parameters) for AlN, GaN, InN and ZnO in the wurtzite phase. For band-energy differences we observe a pronounced nonlinear dependence on strain. Consistent and complete sets of deformation potentials are then derived for realistic strain conditions in the linear regime around the experimental equilibrium volume. To overcome the limitations of density-functional theory in the local-density and generalized-gradient approximations we employ the Heyd-Scuseria-Ernzerhof hybrid functional as well as exact exchange (OEPx)-based quasi-particle energy calculations in the G₀W₀ approach.