Dragomir Adrian, Nikogosyan David N, Zagorulko Konstantin A, Kryukov Peter G, Dianov Evgueni M
Department of Physics, National University of Ireland, University College Cork, Cork, Ireland.
Opt Lett. 2003 Nov 15;28(22):2171-3. doi: 10.1364/ol.28.002171.
We report on what is to our knowledge the first fabrication of fiber Bragg gratings by UV femtosecond radiation. The Bragg gratings, with photoinduced refractive-index modulation up to 1.92 x 10(-3) in H2-loaded SMF-28 and up to 1.05 x 10(-3) in Nufern GF1 fibers, were written by high-intensity (31-77-GW/cm2) femtosecond pulses at 264 nm. The dependence of the refractive-index modulation on intensity at equal fluences points to a two-photon absorption mechanism for grating inscription.
