Design and Investigation of Gamma Ray Dosimetry with Doped Polymer-Infused Porous Silicon Annular Photonic Crystal

This research explores a modified photonic crystal structure called the annular photonic crystal (APC) for enhanced gamma ray detection, specifically in the range of 0 Gy to 70 Gy. The APC design is primarily based on porous silicon and a polyvinyl alcohol (PVA) polymer that is doped with crystal violet (CV) and carbol fuchsine (CF). The selection of these materials is motivated by their significant changes in refractive index when exposed to gamma ray doses. Detection relies on the appearance of a resonant peak in the reflectance spectrum of the structure, which arises from a defect layer created by the PVA polymer doped with CV and CF dyes at the center of the structure. To analyze the variations in the defect mode characteristics within the reflectance spectrum at different gamma ray doses, a modified transfer matrix method is utilized. Various geometric parameters of the structure are meticulously optimized to achieve optimal sensing performance. This hybrid structure enhances the interaction efficiency between the incoming radiation and the photonic crystal matrix, resulting in a notable sensitivity of 227.19 nm/RIU. Additionally, the proposed sensor is easy to fabricate and can be readily integrated with other photonic devices, making it an ideal candidate for dosimetry applications in medical treatments, radiation protection, and industrial processes.