Direct energy transfer and migration among Cr ions in the Cr, Nd:GSGG luminescent system

Abstract Two sets of experimental data of the chromium emission, at short and long times, for the non-radiative energy transfer processes in Cr, Nd:GSGG (Gd 3 Sc 2 Ga 3 O 12 ) are analyzed. In contrast to previous analysis, our modeling allows calculating the whole fluorescent transient, that is, it is not divided into three time regimes, as current models do, nor a cut-off distance is introduced. The observed fast initial decay is due to a sum of multipolar and exchange interactions among dopants while for longer times the migration of energy among Cr ions cannot be neglected. Our analysis is based on solving the corresponding master equations that govern the non-radiative energy transfer processes among dopants. The used free parameters for our calculations are identical to those used in current models and for our analysis the corresponding values were independent of the dopants concentration.