A novel method for extracting oscillator strength of select rare-earth ion optical transitions in nanostructured dielectric materials

A new technique to obtain the oscillator strength of select rare-earth optical transitions in nanostructured dielectric materials (nanophosphors) is presented. It is based on the experimentally observed nanophosphor lifetime dependence on the embedding medium. A constant oscillator strength and parity-allowed electric dipole transitions of the RE ion emission are assumed. The oscillator strength is obtained from the slope of the 1/tau(ij) vs. n(n(2) + 2)(2) plot, where tau(ij) is the radiative lifetime of transition between states i and j, and n is the index of refraction of the embedding medium. The use of the technique is illustrated for the Y2SiO5:Ce nanophosphor. (c) 2006 Elsevier Ltd. All rights reserved.