Analysis of a gold coated plasmonic sensor based on a duplex core photonic crystal fiber

Abstract

An exploration of a gold-coated dual-core with hexagonally arranged circular air holes SPR-PCF sensor is presented in this paper. Chemically inactive and stable material gold is provided as plasmonic material in this design. Placement of the gold layer outside of the PCF structure simplifies the detection process of this sensor and also assures fabrication feasibility. The performance of this sensor is investigated in terms of wavelength sensitivity, amplitude sensitivity, resolution, sensor length and linearity response by using the Finite Element Method (FEM) based COMSOL Multiphysics software. Maximum wavelength sensitivity is found to be 10,700 nm/RIU for analyte sensing range between 1.39 to 1.40 by using wavelength interrogation method as well as maximum amplitude sensitivity reaches about 1770 RIU-1 for analyte RI 1.39 by using amplitude interrogation method. Besides, the sensor's resolution is found to be 9.34×10-6. The outcome of alternating structural parameters such as gold layer thickness, pitch, air hole diameter, different shapes of air hole in the core is also discussed as well. The reported sensor might be a fruitful aspirant in the field of biological sample detection, organic chemical sensing and biomolecule recognition. Keywords: Photonic crystal fiber, Plasmonic, Analyte, SPP, Resolution, RI