Abstract

As a key component for today’s and future wavelength division & multiplexing (WDM) telecommunication network, fibre Bragg gratings (FBGs) have been heavily studied for one decade The thermal stability is one of the more important topics because of the request for the reliability of components [1][2] It is known that there is a thermal decay process of the reflectivity after the inscription of FBGs and the accelerated aging is proposed as a useful way to stabilize the spectral characteristics [1] Another interesting method to improve the stability was suggested by E Salik, et al [2] They showed a higher thermal stability in reflectivity for the unsaturated FBGs when the fibre is uniformly illuminated with UV light (e g 334nm and 244nm, one-photon photosensitive process) before, during, or after grating fabrication Up to now, there is still no work to focus on the decay of the Bragg wavelength (B W) of FBGs, which is another key factor for the WDM components

© 2000 IEEE