High-performance surface plasmon resonance fiber sensor based on cylindrical vector modes

Area of Science:

• Optoelectronics
• Nanophotonics
• Biomedical Sensing

Background:

• Surface Plasmon Resonance (SPR) sensors are crucial for label-free biosensing.
• Photonic Crystal Fibers (PCFs) offer unique light-confining properties for enhanced sensing.
• Developing high-sensitivity sensors for early cancer detection is a significant challenge.

Purpose of the Study:

• To propose and design a novel SPR sensor utilizing a circular photonic crystal fiber (C-PCF).
• To employ cylindrical vector modes with azimuthal polarization for enhanced sensor performance.
• To achieve high sensitivity and resolution for detecting low concentrations of cancer biomarkers.

Main Methods:

• Design of a C-PCF with a specific air hole arrangement and a 44 nm gold coating.
• Utilization of the finite-element method (FEM) to optimize geometric parameters.
• Analysis of sensor performance for analytes with refractive indices (RI) from 1.29 to 1.34.

Main Results:

• Achieved a maximum sensitivity of 13,800 nm/RIU at RI = 1.33-1.34.
• Obtained a sensor resolution on the order of 10^-6.
• Recorded the highest reported amplitude sensitivity of 2380 RIU^-1 at RI = 1.30.
• Demonstrated high performance with a simple sensor design.

Conclusions:

• The proposed C-PCF based SPR sensor demonstrates exceptional sensitivity and resolution.
• The sensor is suitable for detecting low concentrations of biomarkers like hemoglobin, aiding cancer diagnosis.
• This design offers a promising platform for advanced biomedical sensing applications.