Multiphonon excitation induced by long-range order crystal-field and short-range order Jahn-Teller distortion effects is observed in Fe-doped semi-insulating InP in the spectral range from 400 to 1100 cm-1 for infrared light propagating in a slab waveguide geometry. Transmission measurement data are analyzed in terms of phonon energies at critical points in the Brillouin zone. The phonon energies obtained are in excellent agreement with recently reported second order Raman scattering spectra and two-phonon absorption measurements of crystalline InP. The energy differences between the nearly degenerate two phonon transverse optical+longitudinal optical transitions at the Γ, X, and L points are also resolved and shown to be 10 cm -1. No localized mode or vibronic level absorption is observed, consistent with the relatively low concentration of Fe impurities in the samples.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)