Magneto-optical study of quantum-well electronic structure using disorder-induced resonant acoustic-phonon Raman scattering

G. GOLDONI, T. RUF, V. F. SAPEGA, A. FAINSTEIN, AND M. CARDONA

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Año: 1995 vol. 51 p. 14542 - 14548

1098-0121

We study the electronic structure of a (100/103)-Å GaAs/Al0.35Ga0.65As multiple quantum-well sample using the resonant enhancement of disorder-induced continuous Raman emission by acoustic phonons at interband magneto-optical transitions between Landau levels. Calculations are compared to fan plots of excitation energy vs resonance magnetic field and material parameters are determined. We find a significant difference between the electron effective mass for confinement (me⊥=0.068m0) and that which describes Landau quantization (me∥=0.073m0). Both masses are enhanced as compared to the bulk value (me=0.0665m0). Our results confirm theoretical predictions on the influence of conduction band nonparabolicity and anisotropy on effective masses in quantum wells.