Energy transfer and relaxation in europium-activated Y2O3 after excitation by ultraviolet photons

Autor: R. L. Simpson, Carleton H. Seager, David R. Tallant
Rok vydání: 2002
Předmět:
Zdroj: Journal of Applied Physics. 91:4053-4064
ISSN: 1089-7550
0021-8979
Popis: We present persistence data from the 5D manifolds of europium (3+)-activated Y2O3, after excitation by ultraviolet photons. For europium concentrations below 1 at. %, the persistence is largely consistent with multiphonon relaxation. For europium concentrations at and above 1 at. %, the persistence shows evidence for energy transfer interactions between europium activators. Interactions involving one activator in an upper (5D3, 5D2 or 5D1) manifold and another in a ground state (7F) manifold affect the kinetics of the relaxation of the upper 5D manifolds but do not degrade phosphor efficiency. Interactions involving two activators in excited manifolds ultimately dissipate, by phonon emission, excitation that might be emitted as photons. The interactions involving two activators in excited manifolds appear to be related to both concentration quenching and the reduction of phosphor efficiency at high excitation density.
Databáze: OpenAIRE