title: Dynamic evolution of the spectrum of long-period fiber Bragg gratings fabricated from hydrogen-loaded optical fiber by ultraviolet laser irradiation.
abstract: Long-period fiber Bragg gratings fabricated by exposure of hydrogen-loaded fiber to UV laser light exhibit large-scale dynamic evolution for approximately two weeks at room temperature. During this time two distinct features show up in their spectrum: a large upswing in wavelength and a substantial deepening of the transmission minimum. The dynamic evolution of the transmission spectrum is explained quantitatively by use of Malo's theory of UV-induced quenching [Electron. Lett. 30, 442 (1994)] followed by refilling of hydrogen in the fiber core and the theory of hydrogen diffusion in the fiber material. The amount of hydrogen quenched by the UV irradiation is 6% of the loaded hydrogen.
authors.affiliation: Faculty of Engineering, Kagawa University, 2217-20 Hayashi-cho, Takamatsu, Kagawa 761-0396 Japan.
authors.forename: Keio
authors.initials: K
authors.lastname: Fujita
authors.forename: Yuji
authors.initials: Y
authors.lastname: Masuda
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nakayama
authors.forename: Maki
authors.initials: M
authors.lastname: Ando
authors.forename: Kenji
authors.initials: K
authors.lastname: Sakamoto
authors.forename: Jun-pei
authors.initials: JP
authors.lastname: Mohri
authors.forename: Makoto
authors.initials: M
authors.lastname: Yamauchi
authors.forename: Masanori
authors.initials: M
authors.lastname: Kimura
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Mizutani
authors.forename: Susumu
authors.initials: S
authors.lastname: Kimura
authors.forename: Takashi
authors.initials: T
authors.lastname: Yokouchi
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Suzaki
authors.forename: Seiki
authors.initials: S
authors.lastname: Ejima