A Plasmonic Photonic Crystal Fiber Based Refractive Index Sensor with Simple Design and High Sensitivity

A fabrication friendly plasmonic sensor based on photonic crystal fiber has been proposed in this study for detection of refractive index of liquid analytes. The design is kept simple and symmetric with small number of periodically arranged air holes and polished surfaces on both sides. Gold is employed on the polished surfaces as plasmonic material. The sensor has a highest wavelength sensitivity of 54200 nm/RIU along with a minimum corresponding resolution of 1.845 × 10^-6 RIU. The maximum figure of merit and the maximum amplitude sensitivity of the sensor is 653 RIU^-1 and 805.9 RIU^-1 respectively. The sensor can sense a wide variety of analytes within the wide refractive index range of 1.30 – 1.42. Given its easy to implement structure and high sensitivity, the proposed sensor can be considered as an outstanding choice for mass production, enabling real-time applications in medical diagnosis, chemical and food industry.