Radiation-induced absorption in bismuth-doped germanosilicate fibres

We have investigated the effect of ionising radiation on the absorption properties of bismuth-doped germanosilicate fibres in the near-IR spectral region. Dynamic dependences of the changes in intensity and structure of the radiation-induced absorption spectra and the kinetics of its relaxation at various temperatures are obtained. A new absorption band is found in the wavelength region of 1.2 μm, which appears in irradiated high-germanium optical fibres doped with bismuth. (paper)