Carbon-acceptor-induced cascade scattering by acoustic phonons above the(e,A0)threshold in GaAs

Below the ${E}_{0}$ band gap of GaAs the transitions of free electrons to bound impurity states play an important role. Our study of Raman scattering above the ${(e,A}^{0})$ threshold at 2 K shows that the electrons are scattered by acoustic phonons before successively being scattered by one LO phonon and finally recombining the holes bound to the acceptors. This finding indicates one of important mechanisms of relaxation of the hot electrons excited above the minimum of conduction band.