Cesium Lead Bromide-Coated Fiber Bragg Grating Sensors for Gamma Radiation Environments

This study presents the development and characterization of CsPbBr₃ (CPB) and CPB-poly-(methyl methacrylate) (CPB-PMMA) composite coatings on Fiber Bragg Grating (FBGs)-based sensors for high-sensitivity gamma radiation sensing. CPB precipitates were synthesized using a solvent-based method and uniformly deposited onto the FBGs. The incorporation of PMMA into the CPB matrix enhanced both mechanical stability and adhesion to the FBG surface. Spectral analysis revealed significant Bragg wavelength shifts in response to gamma radiation exposures, indicating strain-optic variations induced by radiation-matter interactions. Comparative investigations between uncoated, CPB-coated, and CPB-PMMA-coated FBGs confirmed that the coatings significantly enhance strain sensitivity and stability. The incorporation of PMMA modified the mechanical response, influencing residual stress and strain attenuation. The advantage of using fiber optic sensors includes the ability to enable multiplexed sensing across large areas, immunity to electromagnetic interference (EMI), and operability in high-temperature environments. Additionally, CPB and CPB-PMMA coatings demonstrated enhanced sensitivity under UV exposure, further highlighting their potential for advanced optical sensing applications in both radiation and UV-intensive environments. These results demonstrate the potential of CPB-based coatings for radiation monitoring in extreme environments, including in nuclear facilities, space missions, and near medical instruments using radiation sources. The findings provide a foundation for further optimization of perovskite-polymer composites to enhance sensor performance and long-term durability in radiation-intensive applications.