Fabrication of long-period fibre grating by CO2 laser-annealing in fibre-drawing process

Long-period fibre grating (LPFG) writing by a CO2 laser-annealing using a fibre-drawing process is demonstrated. The fibre in the drawing process was irradiated periodically by a CO2 laser to modify the refractive index. An LPFG with transmission loss of - 10 dB and full width at half-maximum of 13 nm has been fabricated. Results show that the refractive index change was induced by stress at the moment of laser annealing.