Seminars and Events‎ > ‎Past Events‎ > ‎

Seminar Announcement: Franck Mady

posted Oct 28, 2019, 4:21 AM by Stefano Varas   [ updated Oct 28, 2019, 4:21 AM ]

Monday, 28 October 2019, 10:00
Sala Grande Palazzina B via alla Cascata 56/C

"Specific mechanisms associated with rare earth dopants (Yb, Er, Ce) in the radiation induced attenuation of silica based optical fibers"

Franck Mady
Université Côte d'Azur, INФNI, Laboratoire de Radieochimie,
Sciences Analytiques et Environnement (LRSAE),
Parc Valrose 06108 Nice, Cedex 2,

We report on an original approach enabling an in depth investigation of the mechanisms of the radiation induced attenuation (RIA) development and annealing in silica based fiber preforms [1]. The experim ental protocol combines temperature and spectrally resolved TSL measurements with the characterization of the RIA annealing in TSL conditions. TSL allows the identification of those dopant or defect related centers that trap free carriers under irradiati on to form color centers (responsible for RIA) and that are restored by recombination during the thermal annealing induced by the TSL readout. The simultaneous monitoring of the RIA bleaching reveals correlations between these reformation processes and the recovery of radiation induced optical absorption bands attributed to well known color centers. Such correlations bring decisive indications on RIA mechanisms.
Our protocol is applied in a systematic manner to silicate, aluminosilicate, Yb doped silicate, Er doped silicate, Yb doped and Yb,Ce codoped aluminosilicate preform samples to elucidate the role played by each dopant.

Stefano Varas,
Oct 28, 2019, 4:21 AM