Electronic States and Optical Gap of Phosphorus-Doped Silicon Nanocrystals Embedded in a Silica Host Matrix
Using the envelope-function approximation the electronic states and the optical gap of silicon nanocrystals heavily doped with phosphorus have been calculated. Assuming the uniform impurity distribution over the crystallite volume we have found the fine structure of the electron ground state (induced by the valley-orbit interaction) and the optical gap as a function of the crystallite size and donor concentration. It is shown that the energy of the ground singlet state decreases almost linearly as the concentration increases, while the valley-orbit splitting increases nonlinearly. Phosphorus doping also results in the decrease of the nanocrystal gap with increasing the impurity concentration.
A. A. Konakov et al., "Electronic States and Optical Gap of Phosphorus-Doped Silicon Nanocrystals Embedded in a Silica Host Matrix", Solid State Phenomena, Vols. 205-206, pp. 486-491, 2014