Fano mode based plasmonic sensor for temperature and chemical pollutant detection

Plasmonic sensors provide great sensitivity to minute quantities of analytes and provide excellent detection. This sensitivity is crucial for applications in biomedical diagnostics, environmental monitoring, and food safety. In this investigation, a plasmonic refractive index sensor based on key ring shaped resonator consisting of a microring resonator and two rectangular resonator is proposed. Finite Difference Time Domain method is used to study the transmittance characteristics of the sensor. The device exhibits quadruple Fano resonance with highest sensitivity of 2521.7 nm/RIU. Other performance parameters such as FOM (Figure of Merit), Q factor and Detection limit are also been calculated, with values 98.8 RIU−1, 99.6 and 0.01 respectively. Additionally, the effects of different geometrical configurations is also studied, providing insights into the design principles in context of potential fabrication complexities. Further, the simulated Fano characteristic is validated against the theoretical value. The application of the proposed sensor is investigated for different types of analyte such as chemical pollutants and temperature sensing.