Tamm resonance-based gamma radiation dosimeter in dye-doped porous silicon photonic structure

Abstract This study introduces a novel gamma radiation dosimeter based on Tamm resonance within a multi-layered photonic crystal structure, designed for high sensitivity and real-time monitoring. The structure comprises alternating porous silicon layers with varying porosities, infiltrated with polyvinyl alcohol polymer doped with crystal violet and carbol fuchsin dyes, a metallic layer, and a substrate, all surrounded by air. Exposure to gamma radiation induces changes in the dye molecular structure, causing measurable shifts in the Tamm resonance resonance peak wavelength in the reflection spectrum, which correlate with radiation-dose. The optical response is modeled using the transfer matrix method and Bruggeman’s effective medium approximation, accounting for radiation-induced refractive index variations in the composite material. Numerical simulations demonstrate a sensitivity of 0.149 nm Gy −1 , a quality factor of approximately 761, and a detection limit of 0.228 Gy, with performance optimized using a silver metallic layer and 15 periods in the PC structure. The design enables normal incidence excitation, eliminating the need for a coupling prism, thus simplifying the optical setup, enhancing stability, and reducing costs. Performance metrics such as figure of merit (0.224 Gy −1 ), signal-to-noise ratio (8.378), and spectral resolution (0.033 nm) underscore the dosimeter’s potential as a compact, non-invasive, and precise alternative to conventional radiation monitoring devices, with applications in medical, industrial, and environmental settings.