Concentration dependence of radiative and non-radiative energy transfers in rare earth ? doped laser crystals grown from a new method based on gradient concentration fibre single crystals

摘要

New and original monocristalline samples having a continuous longitudinal concentration gradient are used to study dynamical processes of resonant transitions in rare earth doped laser crystals like Y_2O_3 sesquioxide and YAG garnet. This fast and simple method allows to measure the radiative lifetime, the influence of radiation trapping, impurity quenching and RE pairs or clusters on the excited-state lifetime as a function of the dopant concentration. Examples in Yb~(3+), Er~(3+) and Ho~(3+) rare earth ions are presented.