FORBIDDEN ONE-LO-PHONON RESONANT RAMAN-SCATTERING AND MULTIPHONON SCATTERING IN PURE CDTE CRYSTALS

We have performed experiments to show the resonant enhancement of the forbidden first-order LO mode at the E0 + DELTA-0 gap of pure CdTe at 17 K. We explain this forbidden scattering in terms of intrinsic intraband Frohlich interaction. In our experiments we also observe multiple-LO-phonon scattering up to four orders under both incoming and outgoing resonant conditions. The multiphonon spectra are briefly discussed and compared with other cadmium chalcogenides.