Dynamic evolution of the spectrum of long-period fiber Bragg gratings fabricated from hydrogen-loaded optical fiber by ultraviolet laser irradiation.
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.
Fujita
Keio
K
Faculty of Engineering, Kagawa University, 2217-20 Hayashi-cho, Takamatsu, Kagawa 761-0396 Japan.
Masuda
Yuji
Y
Nakayama
Keisuke
K
Ando
Maki
M
Sakamoto
Kenji
K
Mohri
Jun-pei
JP
Yamauchi
Makoto
M
Kimura
Masanori
M
Mizutani
Yasuo
Y
Kimura
Susumu
S
Yokouchi
Takashi
T
Suzaki
Yoshifumi
Y
Ejima
Seiki
S