Article révisé par les pairs
Résumé : The implementation of Wavelength Division Multiplexing (WDM) techniques in fiber optic data-communication links for nuclear installations requires to assess the radiation tolerance of passive WDM multiplexers. Nowadays, Fibre Bragg gratings (FBG) have become a key component in all-fibre WDM multiplexers. Up to now, only accelerated short term irradiation experiments of FBG filters have been discussed, suggesting possible ways to optimise their radiation tolerance. In this paper, we evaluate the long-term behaviour of FBGs filters, written in different types of optical fibres, after two years of continuous low-dose rate gamma-neutron irradiation. We compare these results with our previous accelerated tests. We evidence that FBG filters can withstand years in a nuclear environment, while keeping their filtering properties at an acceptable level.