Selective excitation luminescence and electronic Raman scattering study of the 78-meV acceptor in GaAs

We observe for the first time two excited states of the 78-meV acceptor in liquid encapsulated Czochralski GaAs with excitation energies of 62.9 and 66.9 meV above the ground state, respectively. These levels were observed in two different samples using selective excitation luminescence and electronic Raman scattering. We conclude that these levels could correspond to transitions from the 1s2 ground state to the split 1s12s1 excited state of a double acceptor.