Anomalies in the concentration quenching of luminescence in doped Y2SiO5:Pr3+ nanocrystals

In Y₂SiO₅:Pr³⁺ nanocrystals, an ordered phase is observed in the ¹ D ₂ luminescence decay curves of Pr³⁺ ions at their anomalously low concentration (0.5 at %). This effect is caused by the predominant accumulation of activator ions near the nanocrystal surface, which provides relaxation of the elastic strains arising as a result of the misfit between the ionic radii of Pr³⁺ and Y³⁺. The concentration quenching of Pr³⁺ luminescence is due to cooperative cross relaxation.