Square array photonic crystal fiber-based surface plasmon resonance refractive index sensor
Abstract
Based on surface plasmon resonance (SPR), a novel refractive index (RI) sensor comprising a square photonic crystal fiber (PCF) is proposed to realize the detection of the annular analyte. Instead of hexagon structure, four large air-holes in a square array are introduced to enhance the sensitivity by allowing two polarization directions of the core mode to be more sensitive. The gold is used as the only plasmonic material. The design purpose is to reduce the difficulty in gold deposition and enhance the RI sensitivity. The guiding properties and the effects of the parameters on the performance of the sensor are numerically investigated by the Finite Element Method (FEM). By optimizing the structure, the sensor can exhibit remarkable sensitivity up to 7250 nm/RIU and resolution of 1.0638 × 10-5 RIU with only one plasmonic material, which is very competitive compared with the other reported externally coated and single-layer coated PCF-based SPR (PCF-SPR) sensors, to our best knowledge.
- Publication:
-
Modern Physics Letters B
- Pub Date:
- December 2017
- DOI:
- 10.1142/S0217984917503523
- Bibcode:
- 2017MPLB...3150352L
- Keywords:
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- Photonic crystal fiber;
- surface plasmon resonance;
- sensor;
- finite element method