Refractive Index Sensing-Based Surface Plasmon Resonance Sensor for Sensitivity Enhancement: Theoretical Analysis

• Published in: Plasmonics (Norwell, Mass.) Vol. 20; no. 8; pp. 6083 - 6094
• Main Authors: Ansari, Gufranullah, Kanjariya, Prakash, Reddy, M. Sudhakara, Choudhury, Satish, Albert, Helen Merina, Kaur, Irwanjot, Rathi, Vikas, Sead, Fadhil Faez, Sharma, Yash, Sinha, Aashna, Uniyal, Arun
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2025; Springer Nature B.V
• Subjects: Biochemistry; Biological and Medical Physics; Biophysics; Biotechnology; Cesium fluorides; Chemistry; Chemistry and Materials Science; Environmental monitoring; Matrix methods; Nanotechnology; Optical properties; Plasmonics; Real time; Refractivity; Sensitivity analysis; Sensitivity enhancement; Silicon nitride; Surface plasmon resonance; Transfer matrices; Zirconium nitrides; Sensitivity; Surface plasmon resonance; Silicon nitride; Zirconium nitride
• ISSN: 1557-1963; 1557-1955; 1557-1963
• DOI: 10.1007/s11468-025-03082-5

Surface plasmon resonance (SPR) sensors are essential for detecting several applications because of their high sensitivity and real-time analysis capabilities. This paper’s proposed sensor incorporates the CsF prism, gold (Au), silicon nitride (Si 3 N 4 ), and zirconium nitride layers to detect the various applications. Au, which has excellent plasmonic qualities, greatly increases sensitivity. Additionally, incorporating Si 3 N and ZrN, which have remarkable optical and electronic properties, improves signal enhancement by increasing light-matter interaction. The proposed sensor analyzes performance using the transfer matrix method (TMM) and Kretschmann configuration, which is based on Fresnel’s equation. At RI of 1.33–1.35 sensing analyte has the following maximum sensitivities (S) and figure of merits (FoM): 281.58, 294.44°/RIU and 38.85/RIU, 45.93/RIU with/without ZrN layer at remarkable minimum reflectance, respectively. According to the study, combining Si 3 N 4 and ZrN materials with conventional plasmonic metals can improve sensitivity while serving as a platform for additional medical diagnostics and environmental monitoring.