Energy transfer at 1500 nm in lead fluoroborate glasses (PbO–PbF2–B2O3) codoped with Er3+ and Yb3+ is studied for the first time to the authors’ knowledge. A sample codoped with 1 mol. % of Yb2O3 and 0.01 mol. % of Er2O3 has a measured fluorescence lifetime of (1.30±0.07) ms and an energy transfer efficiency of 80%. Also, a large emission band, of 72.4 nm has a measured peak emission cross section of (0.73±0.06)×10−20cm2. The calculated Judd–Ofelt parameters are Ω2=(3.51±0.14)×10−20 cm2, Ω4=(1.09±0.07)× 10−20 cm2, and Ω6=(0.94±0.07)×10−20 cm2. The temporal evolution of the Yb3+ fluorescence is fitted by use of the Yokota–Tanimoto expression to yield the Yb3+ diffusion constant [(1.6±0.2)×10−10 cm2 s−1] and the critical radius of Yb3+/Er3+ (18±1)×10−8 cm. Results with the singly doped samples produced are presented to clarify the energy transfer process.
© 2002 Optical Society of America
(140.3380) Lasers and laser optics : Laser materials
(160.2750) Materials : Glass and other amorphous materials
(160.3380) Materials : Laser materials
(160.4760) Materials : Optical properties
(160.5690) Materials : Rare-earth-doped materials
Luciana Reyes Pires Kassab, Lilia Coronato Courrol, Alessandro Santos Morais, Sonia Hatsue Tatumi, Niklaus Ursus Wetter, and Laércio Gomes, "Spectroscopic properties of lead fluoroborate glasses codoped with Er3+ and Yb3+," J. Opt. Soc. Am. B 19, 2921-2926 (2002)