Papers - accepted for presentation Proceedings »
Photonic Crystal Fiber-Based Surface Plasmon Resonance Sensor for Sensing Broad Range of Refractive Indices
A twin core photonic crystal fiber-based surface plasmon resonance sensor has been designed in this work to detect a wide range of refractive indices with high sensitivity. The dual core fiber is polished on both sides and the metal layer is deposited around it as the plasmonic layer. A microchannel is formed on each side between the cores and thus the sensor forms four separate plasmonic layers on the external surface of the fiber which helps to achieve a wide detection range. Plasmonic material silver is used here due to its availability and low cost. A thin layer of TiO2 is used on top to prevent oxidation of silver. The proposed design is easy to fabricate and exhibits a good fabrication tolerance. The sensing application is also convenient as the analyte is placed outside the fiber. The analyte refractive index detection range of this sensor is found 1.23 – 1.44. The maximum spectral sensitivity of the sensor is 28200 nm/RIU and the corresponding resolution is 3.55×10^-6 RIU. The maximum amplitude sensitivity of the sensor is 286 RIU^-1. Due to its high sensitivity and wide detection range this sensor can be used to detect various low refractive index (1.23 – 1.29) chemicals (like halogenated anesthetic agents, refrigerants, different type of aerogels) to various bio materials (bio-logical tissues, cancerous cells, hemoglobin) which refractive indices usually lie in the range of 1.3 – 1.39, to various high index (1.4 – 1.44) analytes (like high concentration of electrolytes, proteins).