Fine structure in the cathodoluminescence spectrum from chromium-doped gallium arsenide

It has been reported previously that chromium in gallium arsenide gives rise to two luminescence bands, one centred around 0.80 eV with a no-phonon line at 0.839 eV, the other centred around 0.56 eV. High-resolution cathodoluminescence measurements are reported which show that the line at 0.839 eV consists of nine components, and that there are three no-phonon components at approximately 0.574 eV associated with the lower energy band. Temperature dependence measurements show that there is no shift in the transition energies in the temperature range 4-25K and indicate that splitting occurs in both the initial and final states of the transitions.