Excitation and de-excitation cross sections for light-emitting nanoclusters in rare earth-doped silicon

The excitation and de-excitation cross sections of light-emitting nanoclusters in rare earth-doped silicon are calculated. Two processes of de-excitation are considered: emission of a photon by the center and transfer of the cluster energy to a scattered electron. The cross sections of these two processes are shown to be large. Therefore, de-excitation has a significant effect on the concentration of excited rare-earth centers in silicon.