Design and numerical analysis of a fractal cladding PCF-based plasmonic sensor for refractive index, temperature, and magnetic field

This paper presents a new fractal cladding PCF-based plasmonic sensor for refractive index (RI), temperature, and magnetic field using a single-polarization, single-peak scanning technique. A layer of gold (Au) is sputtered on the outer circular surface of the PCF for direct RI sensing. One-half of the outermost air holes are filled with a temperature-sensitive fluid, and the other half with a magnetic-field-sensitive liquid. An in-depth analysis and numerical examination of the coupling behavior and sensing features are presented by the finite element method (FEM). In the infrared wavelength interval from 1.40 mu m to 1.80 mu m, the RI sensing benchmarks in the 1.40-1.46 range indicate a maximum wavelength sensitivity of 3000 nm/RIU and a maximum amplitude sensitivity of 362.67 /RIU. The wavelength resolution associated with RI is 3.33 x 10(-5) RIU. The benchmarks for temperature sensing show maximum values of amplitude sensitivity, wavelength sensitivity, and resolution of 24.46/degrees C, - 1.2 nm/degrees C, and 8.33 x 10-2/degrees C respectively, from 0 degrees C to 75 degrees C. Finally, the magnetic field sensing benchmarks show 103.52/Oe, 0.67 nm/Oe, and 1.0 x 10 (-4) Oe as maximum values for amplitude sensitivity, wavelength sensitivity, and resolution, respectively, in the range of 5-200 Oe. The proposed fractal cladding PCF-based plasmonic sensor can potentially be deployed as a lab-on-a-PCF for a variety of applications, including hyperthermia monitoring, medical and chemical sample analysis, biomolecular engineering, climatology, magnetocardiography, and magnetomyography.