Development of large-core Yb 2 O 3 -doped yttria-alumino-silicate nanoparticles-based optical fibers

Abstract

ABSTRACT Yb 2 O 3 doped high yttrium alumino-silicate nano-particles based D- and pentagonal (P-) shaped optical fibers having core diameter around 30.0-35.0 µm have been obtained through the conventional modified chemical vapour deposition (MCVD) process and solution doping (SD) technique using thin wall tubes of CSA, around 58-60 mm 2 , followed by enlargement of the inner deposition surface area under suitable pressurization. The process parameters at the different stages of preform fabrication have been optimized in order to obtain the uniform distributions of Al, Yb, and Y along the core diameter. Nano-particles were synthesized under soaking of the porous phospho-silicate core layer in a solution of optimum strength of ytterbium chloride, yttrium chloride, and aluminum chloride. The size of nano-particles was maintained within 5-10 nm under doping of 0.2 mol.% of fluorine. The EDX data reveal that the nano-particles are rich in yttria-alumino-silicate phase and dispersed uniformly. The novelty of this technique involves the direct synthesis of rare-earth doped phase-separated nano-partic les within the large core of optical fiber. The critical fabrication parameters of the process along with the nano-structuration results and spectroscopic properties are highlighted.