We report the resonance of the first-order Raman scattering by longitudinal and transverse optical phonons in GaAs very near to the E0 band gap at 100 K. The resonance enhancement observed at E0 for deformation-potential (TO,LO) and Fröhlich-interaction-induced (LO) scattering is about 100 times larger than calculated for uncorrelated electron-hole pairs. The effect is attributed to the Coulomb correlation of discrete and continuum excitons and agrees with Martins calculation of these effects. The Faust-Henry coefficient is found to be nearly independent of frequency in the region of our measurements (C=-0.60.2).
ASJC Scopus subject areas
- Condensed Matter Physics