Luminescence of Yb3+ ions in silica-based glasses synthesized by SPCVD

The spectra and decay kinetics of Yb3+ single-ion and cooperative luminescence in silica-based optical slab waveguides are investigated. The slab waveguides with a high content of Yb and various amounts of P and Al additives to the light-guiding core glass were fabricated on the basis of fused and unfused glassy layers synthesized via surface-plasma chemical vapor deposition (SPCVD). Luminescence was pumped by laser diodes at ∼904 nm and ∼967 nm wavelengths and recorded in the 450-1175 nm spectral band. For the pure silica host doped with Yb, only the influence of cluster sizes on the luminescence decay kinetics is determined. It is found that the profusion of deposited glass with increased Al content favors separation by geometry of the Yb3+ and Tm3+ ions; the latter are present in the glass as an uncontrollable contamination. Evidence was found that at least two different types of Yb clusters were formed in P doped silica as a result of profusion.