Radiation hardening of silica glass through fictive temperature reduction

Abstract

The aim of this article was to report the effects of c-radiation on type-I Infrasil silica glass with different fictive temperatures, T f , for harsh environment applications. Radiation-induced attenuation in the visible range is found to be much lower in low fictive temperature samples. Photoluminescence experiments show that glasses with higher fictive temperatures have a higher nonbridging oxygen hole centers defect concentration generated by irradiation. In addition, electron paramagnetic resonance studies reveal higher E' point defects, AlOHC, and hydrogen(II) defects in high T f samples. In general, we find that the c-radiation "hardness" of Infrasil301 silica glass becomes significantly higher with decreasing fictive temperature. K E Y W O R D Sdefects, fiber materials, fictive temperature, radiation resistance, silica

Extreme Radiation Sensitivity of Ultra-Low Loss Pure-Silica-Core Optical Fibers at Low Dose Levels and Infrared Wavelengths

“…All the works reported so far in the literature [ 8 , 34 , 35 , 36 ] would have led to the conclusion that the ULL-PSC OFs, as the one here investigated, having lower fictive temperature than the more classical F-doped samples, should be the most radiation-hardened fibers among all the types and that the concentration of the radiation-induced STHs in such fibers should be very low. However, the experimental results, here reported, did not lead to the same conclusion.…”

“…The RIA, indeed, depends on the fiber composition, but also on other parameters such as the fiber treatment (i.e., a pre-loading with H 2 , the irradiation conditions such as particle type, dose, dose-rate, irradiation temperature), and the injected light power, which can bleach radiation-induced point defects [ 5 ]. Basically, for pure silica core fibers, the radiation response also depends on the glass fictive temperature and the presence of impurities such as hydroxyl groups and chlorine traces [ 8 , 9 , 10 ]. As a consequence, it is interesting to investigate how the ULL-PSC fiber optimization in terms of intrinsic attenuation and Rayleigh scattering loss reduction at 1.55 µm could have affected its steady state radiation response in terms of RIA.…”

Recent advances in radiation-hardened fiber-based technologies for space applications

“…Regarding the radiation-hardened optical fibers, from previous research, pure-silica cores, fluorine-doped cores (both with F-doped cladding) and nitrogen-doped optical fibers are the most radiation-hardened optical fibers up to 100 kGy[209][210][211][212] for steady state irradiation. Optimization of these fibers is still possible to enhance their radiation resistance, but implies the fine control of their fabrication process parameters-in particular the glass stoichiometry and fictive temperature-in order to control the nature and concentration of the point defects responsible for their degradation, such as chlorine-related impurities and self-trapped holes and excitons (STEs, STHs)[186,213]. It should be noted that some of these fibers are today commercially available from manufacturers such as Fujikura[214], IXBlue Photonics [215] or Prysmian [216].…”