Abstract

We propose the fabrication of the long-period fiber gratings (LPFGs) in a panda polarization-maintaining fiber (PMF) using a two-step ${\mathrm{CO}}_2$ laser writing method. The first laser irradiation was aligned along one of the axes of the PMF and the grating with high contrast can be written after several laser scannings. The second irradiation was performed by rotating the PMF so that the other axis of the fiber aligns toward the laser exposure. New transmission dips can be observed when the first irradiation is along the slow axis and the second one is along the fast axis of the PMF. The stress relaxation effect of the stress-applying parts due to the laser heating was investigated theoretically and experimentally, which is believed to be dominant for the fabrication of the LPFGs in the PMFs by a ${\mathrm{CO}}_2$ laser.

© 2017 Optical Society of America

Effect of asymmetric stress relaxation on the polarization-dependent transmission characteristics of a CO₂ laser-written long-period fiber grating

Hyung Suk Ryu, Yongwoo Park, Seong Tae Oh, Youngjoo Chung, and Dug Young Kim
Opt. Lett. 28(3) 155-157 (2003)

Measurement of CO₂-laser-irradiation-induced refractive index modulation in single-mode fiber toward long-period fiber grating design and fabrication

Yanjun Li, Tao Wei, John A. Montoya, Sandeep V. Saini, Xinwei Lan, Xiling Tang, Junhang Dong, and Hai Xiao
Appl. Opt. 47(29) 5296-5304 (2008)

Asymmetric transverse-load characteristics and polarization dependence of long-period fiber gratings written by a focused CO₂ laser

Yiping Wang, Dong Ning Wang, Wei Jin, and Yunjiang Rao
Appl. Opt. 46(16) 3079-3086 (2007)

Fabrication of helical long-period fiber gratings by use of a CO₂ laser

Seungtae Oh, Kyung Rok Lee, Un-Chul Paek, and Youngjoo Chung
Opt. Lett. 29(13) 1464-1466 (2004)

Long-period fiber gratings fabricated by use of defocused CO₂ laser beam for polarization-dependent loss enhancement

Minwei Yang, Yuhua Li, and D. N. Wang
J. Opt. Soc. Am. B 26(6) 1203-1208 (2009)