Impact of rare earth element clusters on the excited state lifetime evolution under irradiation in oxide glasses.

Rare earth doped active glasses and fibers can be exposed to ionizing radiations in space and nuclear applications. In this work, we analyze the evolution of (2)F(5/2) excited state lifetime in Yb(3+) ions in irradiated aluminosilicate glasses by electrons and γ rays. It is found that the variation of lifetimes depends on the Yb(3+) clusters content of the glasses for irradiation doses in the 10(2)- 1.5∙10(9) Gy range. In particular, glasses with high clustering show a smaller decrease in lifetime with increasing radiation dose. This behavior is well correlated to the variation in paramagnetic defects concentration determined by electron paramagnetic resonance. This effect is also observed in Yb(3+) doped phosphate and Er(3+) doped aluminosilicate glasses, inferring that clustering plays an important role in irradiation induced quenching.