Multiphonon resonant Raman scattering in non-polar GaN epilayers Available to Purchase

Multiphonon resonant Raman scattering in non-polar a-plane $(112¯0)$ GaN epitaxial layers grown on sapphire substrate were investigated. We report longitudinal optical phonon overtones up to seventh order in a-plane GaN epilayer, which has rarely been observed earlier in GaN. However, for high quality polar c-plane $(0001)$ GaN epilayer and semi-polar r-plane $(112¯2)$ GaN epilayer, resonant Raman spectra were not very prominent. Strong multiphonon resonant Raman scattering process is explained by exciton-mediated multiphonon Raman scattering and defect-induced Fröhlich interaction.