Magnetic-Field-Enhanced Raman Scattering by Confined and Interface Phonons in Semiconductor Superlattices

摘要

Magnetic fields perpendicular to the layers in GaAs-Al(x)Ga(1-x)As superlattices lead to a dramatic enhancement of Raman scattering by confined LO phonons, and also to strong forbidden backscattering by interface modes. Results are consistent with a scattering mechanism involving Frohlich coupling to phonons with wave-vector components in the plane of the layers and photoexcited carriers which account for the breakdown in momentum conservation.