Violet phosphorus-enhanced plug-and-play double-lane fiber optic SPR refractometer

The fiber optic surface plasmon resonance (SPR) technologies can directly detect the change of refractive index on sensor caused by interaction biochemical molecules. Fiber SPR have advantages small size, low cost, no labeling, high sensitivity, and are easy to realize miniaturization, multi-parameter, real-time in-situ detection. Two types probe-type refractometers constructed based novel two-dimensional nanomaterial, i.e., violet phosphorus (VP), mature fabrication characterization technologies. processes firstly introduced, then feasibility is verified via multiple methods. In terms signal demodulation, noise spectrum suppressed variational mode decomposition algorithm, wavelength interrogated monitored in real time centroid method. sensing performance near-field enhanced coated with different layers VP investigated. As increase layer number, exhibits redshift broadening sensitivity enhanced. nearly guided wave refractometer also range 1.33−1.34 corresponding low-concentration biological solution, figure merit structure core/VP dielectric layer/Au layer/sample achieve up 2335.64 nm/RIU 24.15 RIU<sup>−1</sup>, respectively, which 1.31 times 1.25 higher than those single Au refractometer, respectively. core/Au layer/VP 2802.06 22.53 1.57 1.16 refractometer. Finally, integrated into a probe double-lane sensing. developed this paper high-sensitivity, plug-and-play detection combination surface/volume indices. provides new idea for multi-type protein molecules heavy metal ions field.