Efficiency and thermal behaviour of cerium-doped fluorozirconate glass fibre Bragg gratings

1.55 mu m Bragg gratings have been written in cerium-doped fluorozirconate glass singlemode fibres through UV illumination at 246 nm. Photoinduced refractive index changes up to 4*10/sup -4/ have been achieved, leading to grating efficiencies close to 100%. Preliminary results on the thermal behaviour of the gratings and realisation of a tunable laser including such a grating are also reported. The ZBLALi (ZrF/sub 4/-BaF/sub 2/-LaF/sub 3/-AlF/sub 3/-LiF:Ce) glass composition was shown to be the most efficient.