Theory of energy transfer between Er3+ ions and carriers confined in Si nanocrystals in SiO2 matrix

A theoretical model of energy transfer between Si nanocrystals and Er3+ ions in SiO2 matrix is presented. The mechanism, based on the Coulomb interaction between carriers confined in nanocrystal and f-electrons of erbium ions, is considered to be responsible for the excitation and quenching of the 1.55  μ m luminescence, and particularly for its recently discovered nanosecond dynamics. It has been shown that phonon-assisted intraband transition of a confined carrier can give rise to erbium transition into the first excited state with characteristic time being in the nanosecond range.