Double-formant PCF-SPR refractive index sensor with ultra-high double-peak-shift sensitivity and a wide detection...

Area of Science:

• Photonics
• Optical Sensing
• Nanotechnology

Background:

• Surface plasmon resonance (SPR) sensors are crucial for detecting changes in refractive index.
• Photonic crystal fibers (PCFs) offer unique light-confining properties for enhanced sensing.
• Developing dual-resonance sensors can improve sensitivity and detection range.

Purpose of the Study:

• To design and optimize a dual-resonance-peak photonic crystal fiber-surface plasmon resonance (PCF-SPR) sensor.
• To evaluate the sensor's performance for refractive index (RI) detection across different wavelength ranges.
• To explore the potential of dual-peak-shift sensitivity (DPSS) for sensing applications.

Main Methods:

• Numerical analysis was employed to design and optimize the sensor structure.
• Key structural parameters including nanowire diameter and air hole dimensions were systematically varied.
• Wavelength detection technology was used to evaluate the sensor's characteristics and sensitivity.

Main Results:

• The optimized sensor exhibits two distinct resonance peaks in the 700-2350 nm and 2350-5550 nm ranges.
• Maximum wavelength sensitivity (WS) reached 54700 nm/RIU within an RI range of 1.24-1.37.
• Maximum dual-peak-shift sensitivity (DPSS) achieved was 95300 nm/RIU, with a high regression coefficient (R² = 0.99993).

Conclusions:

• The designed dual-resonance PCF-SPR sensor demonstrates high sensitivity and accuracy for refractive index detection.
• The sensor's unique dual-peak characteristics and high sensitivity offer advantages over single-peak sensors.
• Potential applications include medical diagnosis, environmental monitoring, and food safety analysis.