Open AccessAll-fiber bandwidth-tunable band-rejection filter based on a composite grating induced by CO_2 laser pulses
Author(s) -
Zhu Tao,
Cuihua Shi,
Yunjiang Rao,
Lingna Shi,
Kin Seng Chiang
Publication year - 2009
Publication title -
optics express
Language(s) - Czech
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.016750
Subject(s) - materials science , optics , fiber bragg grating , grating , fiber laser , long period fiber grating , bandwidth (computing) , polarization maintaining optical fiber , optoelectronics , optical fiber , fiber optic sensor , telecommunications , physics , wavelength , computer science
We propose an all-fiber band-rejection filter with a tunable bandwidth, which is realized by putting a normal long-period fiber grating in series with a rotary long-period fiber grating written in a twisted single-mode fiber by CO(2) laser pulses. Bandwidth tuning is achieved by applying torsion to the composite grating. Our experimental filter shows a bandwidth tuning of approximately 16.3 nm at a rejection level of approximately 15 dB and a polarization-dependent loss lower than approximately 0.9 dB.