Highly sensitive selectively coated photonic crystal fiber-based plasmonic sensor.

Area of Science:

• Photonics and Sensor Technology
• Plasmonics
• Nanotechnology

Background:

• Miniaturized and highly sensitive sensors are crucial for real-time analyte detection.
• Existing sensors often face limitations in sensitivity and real-time capabilities.

Purpose of the Study:

• To propose a novel, highly sensitive plasmonic sensing scheme utilizing miniaturized photonic crystal fibers (PCFs).
• To enhance sensor performance through a large cavity and birefringence in PCFs for efficient surface plasmon polariton (SPP) excitation and analyte infiltration.

Main Methods:

• Utilized finite element method (FEM) to investigate guiding properties and sensing performance.
• Fabricated the proposed PCFs using the stack-and-draw fiber drawing technique.
• Employed wavelength and amplitude sensing techniques to evaluate sensor performance.

Main Results:

• Achieved maximum sensitivities of 11,000 nm/RIU (wavelength) and 1,420 RIU⁻¹ (amplitude).
• Demonstrated maximum sensor resolutions of 9.1×10⁻⁶ RIU and 7×10⁻⁶ RIU for wavelength and amplitude sensing, respectively.
• Attained a maximum figure of merit (FOM) of 407 and detected analyte refractive indices from 1.33 to 1.42.

Conclusions:

• The proposed PCF-based plasmonic sensor offers high sensitivity, resolution, and a wide detection range.
• The sensor's design, incorporating a large cavity and birefringence, enhances performance for real-time analyte detection.
• Potential applications include medical diagnostics, biomolecule detection, and chemical analysis.