Polaron Effects of Exciton in Wurtzite GaN/AlN Parabolic Quantum Well

The anisotropies of the band mass of holes and the optical phonon mode,and the effect of phonon frequency changing with vector are considered in a wurtzite GaN /AlN parabolic quantum well(PQW).The ground state energy and the binding energy of an exciton in a wurtzite GaN /AlN PQW are calculated by a LLP variational method.The results show that the ground state energy and the binding energy of a heavy-hole exciton or a light-hole exciton in a wurtzite GaN/AlN PQW decreases when the well width increases.The binding energy of an exciton with the effect of polaron are significantly smaller than the results of a bare exciton.The ground state energy and the binding energy of a heavy-hole exciton are less than the corresponding values of a light-hole exciton.The ground state energy of an exciton in wurtzite PQW is less than the results for a Zinc blende PQW.The binding energy of an exciton in wurtzite PQW is larger than the results for a Zinc blende PQW.