Design and Numerical Analysis of a One-Dimensional Photonic Crystal Biosensor for Detection of SARS-CoV-2

This paper presents an investigation of a one-dimensional photonic crystal (1D PC) biosensor with a defect layer for the detection of COVID-19 (SARS-CoV-2). A 1D photonic crystal is composed of silicon dioxide (SiO₂) and titanium dioxide (TiO₂) with a central defective layer. The defect layer was considered as a healthy and infected blood sample. The different refractive indices of the samples caused a shift in the transmission peak, which could be used for the detection of COVID-19 (SARS-CoV-2). The impedance approach was used to calculate the transmittance spectrum of the biosensors. The effects of variation in the defect layer thicknesses and the number of periods on the sensor performance were investigated and optimized to maximize the sensitivity. The sensitivity, quality factor, and detection limit of the biosensor were 3805.5043 nm/RIU, 0.1569 × 10³, and 0.7832 × 10⁻³ RIU. The sensor proposed in this study is suitable for easy fabrication, cost-effective, and highly sensitive sensor designs for biomedical applications.