Radioluminescence and spectroscopic properties of proton-irradiated Yb³⁺ doped crystals embedded in phosphate glass for real-time dosimetry

Abstract

Yb3+ doped phosphate glass and composites containing Yb2Si2O7, LiNbO3:Yb3+, and CaWO4:Yb3+ crystals embedded in phosphate glass were irradiated with a 3.5 MeV proton beam to investigate the impact of the radiation treatment on the Yb3+ spectroscopic properties. While the structure of the Yb3+ doped glass remained almost unaffected by the proton exposure, the irradiation was found to lead to structural changes in the composites, including defect formation and partial dissolution of the crystals with variations in the local environment of the Yb3+ ions. Micro-Raman spectroscopy revealed structural modifications induced by irradiation, including radiation-induced crystallization within the glass phase of the composite, as well as changes in the Raman spectra of the embedded crystals. Despite these microscopic changes, no visible alterations in transparency nor coloration were observed, demonstrating the composites' resistance to 3.5 MeV proton beam. The radioluminescence spectra were measured in-situ and changes in the spectroscopic properties were observed from all samples, with Yb3+ doped glass exhibiting the highest sensitivity with accumulated dose, followed by the composites prepared with CaWO4:Yb3+ and Yb2Si2O7. These results highlight the impact of proton irradiation on the structural and spectroscopic properties of Yb3+ doped crystals embedded in phosphate glass, demonstrating their potential for real-time radiation dosimetry.