Luminescence and scintillation characteristics of Ce3+ and Tb3+ co-doped SiO2 fiber for low-dose gamma radiation

Abstract

Ce³⁺ and Tb³⁺ co-doped SiO₂ optical fibers (SCTF) were prepared using the modified chemical vapor deposition method. The optical and structural properties of the SCTF samples were investigated using refractive index measurements, energy dispersive X-ray spectroscopy, photoluminescence (PL), transmission loss, and fluorescence lifetime. The SCTF was fabricated into a radiation dosimeter, and its gamma radioluminescence (RL) response was studied over a dose rate range of 424.27 to 2095.16 mGy/min and a total dose range of 424.27 to 2095.16 mGy. The radiation response exhibited good linearity. To verify the repeatability of the dosimeter, repeated experiments were conducted at a fixed dose rate of 2095.16 mGy/min. The results demonstrated that the dosimeter has good repeatability. An energy transfer model in SCTF was established, and Ce/Tb-doped SiO₂ was prepared using a sol-gel method. The energy transfer model was verified by measuring its PL spectrum. The above results verify that the SCTF shifts the RL to a longer wavelength due to the energy transfer of radioluminescence, which is more conducive to the remote sensing and transmission of SiO₂ optical fiber in an irradiated environment.