Geometrical effects in the energy transfer mechanism for silicon nanocrystals and Er~(3+)

摘要

Silicon nanoclusters (NCs) strongly sensitize the luminescence of Er~(3+) ions. Attempts to calculate the interaction distance have assumed that the Forster [Ann. Phys. 437, 55 (1948)] and Dexter [J. Chem. Phys. 21, 836 (1953)] relationships for point-to-point energy transfer can be applied to experiments based on multilayered thin-film specimens. Here, the effective finite plane-to-plane relationships are derived for both interaction mechanisms. These relationships show that energy transfer can result from the Forster interaction despite the fact that the measured luminescence intensity varies much more weakly with NC-Er~(3+) separation than predicted by theory for point dipoles. An effective energy transfer distance is found for the NC-Er~(3+) system.