Document Type : Research
Authors
1 1Department of Electrical Engineering, Sara.C., Islamic Azad University, Sarab, Iran
2 Departement of Electrical engineering, Ara. C., Islamic Azad University, Jolfa, Iran
3 3. Assistant Prof., Department of Physics, Yadegar.C., Islamic Azad University, Tehran, Iran
Abstract
Non-invasive and accurate monitoring of glucose plays a crucial role in the management of diseases such as diabetes. In this study, a surface plasmon resonance (SPR)-based biosensor with a multilayer structure in the Kretschmann configuration is designed and optimized. The proposed structure consists of a CsF prism, a silver layer as the plasmonic metal, black phosphorus as the two-dimensional sensing material, and a zinc oxide (ZnO) layer as a protective coating to enhance chemical stability and optical response. The theoretical performance analysis of the sensor is carried out using the transfer matrix method (TMM), and key performance metrics including minimum reflectivity, angular sensitivity, detection accuracy, and figure of merit (FOM) are extracted. The results indicate that the optimized thickness of the silver layer provides a favorable balance between resonance intensity and measurement accuracy. Furthermore, the effect of the number of black phosphorus layers is investigated. Although increasing the number of layers significantly enhances the sensitivity (up to approximately 480 deg/RIU), it also leads to a broader resonance dip and reduced response quality. Therefore, structures with 5 to 6 layers offer optimal performance. The inclusion of the ZnO layer not only improves chemical stability but also enhances the electromagnetic field distribution and overall sensor efficiency. Overall, the proposed biosensor demonstrates high sensitivity and suitable accuracy, making it a promising candidate for non-invasive glucose monitoring in urine samples and advanced applications in biomedical diagnostics.
Keywords
)