Modeling of pair-induced quenching in erbium-doped silicate fibers

Abstract
It is shown that in low-concentration erbium-doped silicate fibers (below 1000 p.p.m.), a residual absorption at 980 nm cannot be saturated. Usual models for upconversion of Er/sup 3+/ cannot match this behavior nor explain a fluorescence lifetime independent of pump power and erbium concentration. A phenomenon, the pair induced quenching (PIQ), that is compatible with the previous experimental results is exhibited. The influence of erbium and aluminum concentration on the ion pair proportion is shown.