Bragg wavelength evolution and thermal sensitivity behaviour of Fibre Bragg Gratings under gamma irradiation

Fibre Bragg gratings (FBGs) can be used as a strain, temperature, external refractive index, … sensor in various domains of application and more particularly in harsh environments such as nuclear plants, radioactive waste storages, and also in a space environment inside artificial satellites. In this study, we report the wavelength and temperature sensitivity radiation response of FBGs written in different optical fibres and thanks to different lasers and methods of inscription. We show that the Bragg wavelength radiation-induced shift depends, in the reported cases, only of the core doping and not of the type of laser, but in all cases, the temperature sensitivity is modified with gamma irradiation.