Concentration self-quenching of luminescence in crystal matrices activated by Nd3+ ions: Theory and experiment

Resonance migration and cross-relaxation processes leading to concentration self-quenching of fluorescence have been studied theoretically and experimentally with Nd3+:LaF3 bulk crystal as an example. The time range of theoretical description of self-quenching kinetics has been expanded by including into consideration the long-range fluctuation stage that determines the slow luminescence quenching of donor centers isolated due to fluctuations of donor surroundings. New experimental data on fluorescence kinetics concentration dependence in a Nd3+:LaF3 bulk crystal are consistently described with single set of energy migration C-DD and cross-relaxation CDA microparameters. The obtained results is the first step to solve the problem of quenching in RE doped nanocrystals where, along with self-quenching, the quenching by additional acceptors namely, various molecular groups, residing in the volume of the nanoparticles have to be accounted.