Electronic structure of nanocrystalline/amorphous silicon: a novel quantum size effect

We report a pseudopotential calculation of a model nanocrystalline Si embedded in amorphous Si up to 13 824 atoms and show a novel quantum size effect in this model system. This large scale pseudopotential calculation has been made possible by a real-time real-space higher-order finite difference method. It is shown that the peaks at around −1 and −2 eV shift to higher energy with decrease in size of nanocrystalline phase.