Research of rapid annealing of fiber Bragg gratings based on arc plasma

In order to realize rapid annealing of fiber Bragg gratings, high temperature arc plasma heat treatment method was adopted. The related experiments were designed for verification. A fiber Bragg grating (FBG) with transmission spectrum depth of 23dB, central wavelength of 1552.09nm and 3dB bandwidth of 0.2784nm was scanned by arc plasma discharging. The results show that the transmission spectrum depth is reduced, the 3dB bandwidth is narrowed and the central wavelength shows blue shift. The variation trend of each parameter is slowed down with the increasing of the repetitive scanning times. Finally, the transmission spectrum depth is reduced by 13dB, the central wavelength is shifted blue by 0.84nm and the 3dB bandwidth is narrowed by 0.1013nm. After fiber grating is annealed in a high temperature furnace for 24h, the transmission spectrum depth, central wavelength and 3dB bandwidth remain the same. It is feasible to use arc plasma for the annealing of FBG with the advantages of short cycle and no damage of the coating layer.