Erbium doped glasses for optical fiber amplifiers Joanna Wójcik, Dominik Dorosz Bialystok University of Technology Wiejska 45D, 15-351 Bialystok, Poland. ABSTRACT The optical and physical properties of three different glass systems were presented. The obtained glasses were doped with 1,75wt% erbium oxide (Er 2 O 3 ). Transmission and luminescence spectra were measured. Absorption spectra were calculated on the basis of transmission spectra. Classic active optical fiber doped with 1,75wt% erbium oxide was fabricated. Attenuation of fabricated optical fiber was measured. Keywords: erbium doped glasses, spectral properties, silica glasses, phosphorus glass 1. INTRODUCTION Rare-earth-doped glasses are very attractive materials for their applications in fiber amplifiers as gain medium. The discovery of the light amplification process in rare-earth doped optical fibers dates back more than 40 years [1]. In 1985 J. Zyskind, R.Giles i E.Desurvire discovered unique properties of erbium as luminescence material. The first erbium-doped fiber laser has been realized in 1986 at Southampton University by Mears et al. The next year the same group of scientists presented results of the first erbium-doped fiber amplifier (EDFA). The maximum of spontaneous emission of erbium is at 1532 nm, which is center the wavelength of third telecommunication window. Therefore erbium-doped optical fibers are so widely used in amplifiers designed for third telecommunication window. Unfortunately clustering effect of erbium ions decreases the concentration of Er 3+ in glass matrices. While, advanced fiber amplifiers to be used in modern WDM systems and other telecommunication areas require higher concentration of erbium ions in order to achieve higher gain. Usually high Er 3+ doping can be realized only in multi-component glasses, such as silica and phosphor glasses, presented in this paper. 2. SAMPLES PREPARATION As the starting materials commercial oxides (>99% pure) were used. Three different glasses with one concentration of erbium oxide (1,75wt%) were obtained, designated as EF, KE and PE, respectively. They are presented in Table 1. Table 1. Compositions and characteristic temperatures of obtained glasses. Sample Glass composition Weight of mixed batches [g] Temperature of removing the OH - [ o C] Melting temperature [ o C] Annealing temperature [ o C] EF SiO 2 – PbO – B 2 O 3 – Na 2 O – K 2 O – Er 2 O 3 15 400 for 15 minutes 1520 460 KE SiO 2 – PbO – B 2 O 3 – Na 2 O – K 2 O – Al 2 O 3 – Er 2 O 3 15 400 for 15 minutes 1350 430 PE P 2 O 5 – Al 2 O 3 – BaO – ZnO – Na 2 O – MgO – Er 2 O 3 15 400 for 15 minutes 1300 400 Additional aluminum oxide (Al 2 O 3 ) in KE glass increases homogeneity of this glass matrix and prevents from clustering. Melted glasses were poured on a pre-heated brass mold. The samples were annealed for 12 hours in furnace, which temperature decreased gradually from the temperature of glass transition to room temperature. Photonics Applications in Astronomy, Communications, Industry,and High-Energy Physics Experiments 2007, edited by Ryszard S. Romaniuk, Proc. of SPIE Vol. 6937, 69371A, (2007) · 0277-786X/07/$18 · doi: 10.1117/12.784676 Proc. of SPIE Vol. 6937 69371A-1