Comment on ‘‘Microscopic theory of optic-phonon Raman scattering in quantum-well systems’’

Huang, Zhu, and Tang [Phys. Rev. B 41, 5825 (1990)] have suggested that Fr\"ohlich scattering by two LO phonons is forbidden in a quantum well in the depolarized configuration, in contradiction with experiments. Here, it is shown that triply resonant depolarized second-order scattering via iterated electron--one-phonon Fr\"ohlich interaction is indeed allowed.