Rare earth (RE) doped optical fibers have shown tremendous progress for producing high power fiber lasers for industrial, medical and strategic applications. However, fabrication of large core, high Yb-doped fiber is still a challenge through conventional process due to poor repeatability and limitation regarding core size. This paper presents successful fabrication of Yb-doped fibers through vapor phase doping technique. Preform fabrication was carried out using a specially constructed MCVD system containing High Temperature Vapor Delivery Unit with sublimators for Al and Yb precursors. The novelty of the present work lies in deposition of Al₂O₃ and Yb₂O₃ in vapor phase simultaneously with silica during formation of sintered core layer which result in uniform dopants distribution in the preform. The fibers exhibited lasing efficiency of 76% with low ‘photodarkening effect’.

Date Published: 3 May 2013
PDF: 5 pages
Proc. SPIE 8775, Micro-structured and Specialty Optical Fibres II, 87750A (3 May 2013); doi: 10.1117/12.2017318

Published in SPIE Proceedings Vol. 8775:
Micro-structured and Specialty Optical Fibres II
Kyriacos Kalli; Jiri Kanka; Alexis Mendez, Editor(s)