A study and comparison of up-conversion luminescence efficiency in four Er~(3+)/Yb~(3+) co-doped glasses

The overlap integrals between the unitary linetypefunction of the fluorescence of the benefactorions and the unitary linetypefunction of the absorbability of the acceptorions in silicate,germinate,phosphate and fluoride glasses are calculated.And the crossrelaxation probabilities in these glasses are calculated as well.The relative populations of the ions in ~4S_(3/2) lever are obtained on the basis of solving transferrateequations.The product of the spontaneous emission probability A61 and the relative populations of the ions in ~4S_(3/2) lever are defined as the up-conversion luminescence efficiency.The conclusion is that luminescence efficiency in fluoride glass is bigger than that in other glasses.The reason is that the radiationless transition probability of ~4S_(3/2) lever in fluoride glass is bigger than that in other glasses.