Overview of the Infrared Radiation Responses of Telecom-grade Single Mode Optical Fibers

We present a comprehensive study about the radiation response of ten single mode optical fibers (SMFs) from three different manufacturers, commercially-available for the telecommunication market. All the SMFs were exposed at room temperature to 100 kV X-rays at two different dose rates, 6 Gy(SiO 2 )/s and 0.6 Gy(SiO 2 )/s, up to 100 kGy and 10 kGy, respectively. Their radiation induced attenuation (RIA) growth and decay kinetics were measured around 1535 nm. The observed RIA levels and kinetics strongly varied between the different samples, allowing to distinguish four different behaviors that are discussed in details. In particular, three of the SMFs exhibit attenuation levels of up to thousands of dB/km at low dose, all pertain to the category of recently developed ultra-low loss pure-silica core SMFs. The RIA kinetics were also found to differ depending on the specifications of the tested fibers: G.652, G.654 or G.657. Spectral measurements in the infrared domain reveal that the most radiosensitive SMFs present infrared absorption bands related to radiation induced point defects created by ionization processes. Our findings demonstrate the potential use and limits of these SMFs in harsh environments for data transfer or sensing. It also reveals how the evolution of the fiber manufacturing techniques pushed by the telecommunication market could affect the fiber radiation response. This also highlights the difficult use of commercial fibers in radiation-demanding applications such as those associated with NewSpace.