We demonstrate a spatially distributed measurement technique to observe temperature changes along a pumped Ybdoped fiber. The technique is based on an array of fiber Bragg gratings acting as temperature sensor line. The Bragg gratings are inscribed directly into the actively doped fiber core using high intensity laser pulses and an interferometric setup. We studied the temperature evolution in differently doped fibers under pumping conditions and find different effects contributing to the observed temperature increase. To avoid an additional heating caused by pump-induced photodarkening, we measure the spatially resolved temperature profile during pumping along a photodarkening-reduced, cerium co-doped fiber.

Date Published: 7 March 2014
PDF: 7 pages
Proc. SPIE 8982, Optical Components and Materials XI, 898206 (7 March 2014); doi: 10.1117/12.2037663

Published in SPIE Proceedings Vol. 8982:
Optical Components and Materials XI
Michel J. F. Digonnet; Shibin Jiang, Editor(s)