Effect of Hydrogen Content on Rare Earth Fluorescence in Lithium Niobate

The unique properties of the rare earth ions make them attractive optoelectronic dopants whose electronic structure varies little by host material. Ubiquitous hydrogen impurities can, however, affect photodynamic processes such a fluorescence. Due to difficulties in material characterization the role and mechanism of rare earth fluorescence quenching by hydrogen remains unclear. We have studied the quenching of erbium(III) and thulium(III) fluorescence in lithium niobate as a function of hydrogen content. By varying the hydrogen content in LiNbO3 by indiffusion processes we were able to control the concentration of hydrogen and the proximity of hydroxyl impurities to the rare earth ions to probe the quenching mechanism. This increased understanding of the relationship between rare earth ion performance and hydrogen will allow for the tailoring of fluorescence lifetimes and selective quenching of individual electronic transitions.