Bragg gratings photoinduced in ZBLAN fibers by femtosecond pulses at 800 nm.
Fiber Bragg gratings were written in thulium-doped and undoped single-mode ZBLAN fibers by focusing femtosecond laser pulses on the fiber core through a phase mask. Maximum index modulation of the order of 1 x 10(-3) was induced in both types of fibers. Measurements of the transverse refractive index changes across the core and cladding regions indicate that the grating formation originates from a negative index change.
Bernier
M
M
Centre d'Optique, Photonique et Laser, Université Laval, Québec G1K 7P4, Canada. martin.bernier.1@ulaval.ca
Faucher
D
D
Vallée
R
R
Saliminia
A
A
Androz
G
G
Sheng
Y
Y
Chin
S L
SL