Local-field correction for intra-4f-configurational transitions of rare earth ions embedded in amorphous chalcogenide solids

The Lorentz-type local-field correction factor based on the virtual-cavity model has been widely applied to describing absorption and emission of photons owing to the intra-4f-configurational transitions of rare earth ions embedded in chalcogenide glasses. From a comparison between the oscillator strengths of Dy3+ ions embedded in Ge–As–S and Ge–Ga–S glasses, however, we verify that the real-cavity model accommodates the observed changes of the oscillator strengths much better than the virtual-cavity model. In addition, effects of chemical environments on the oscillator strengths are discussed in connection with local structural information obtained from Dy L3-edge extended X-ray absorption fine structure spectroscopic analysis.