The effects of gamma-radiation on the properties of Brillouin scattering in standard Ge-doped optical fibres

We have experimentally studied the effects of gamma-radiation up to very high total doses on the physical properties of Brillouin scattering in standard commercially available optical fibres. A frequency variation of about 5 MHz for both Brillouin frequency and linewidth has been measured at the total dose of about 10 MGy. The radiation-induced shift has a negligible practical impact and makes Brillouin scattering very immune to radiation, so that distributed sensors based on this interaction exhibit an interesting potential for use in nuclear facilities.