High index core flat fiber surface plasmon resonance bio-sensor.

Area of Science:

• Photonics
• Nanotechnology
• Biomedical Engineering

Background:

• Photonic crystal fibers offer design flexibility for efficient plasmonic biosensors.
• Miniaturized biosensors are crucial for advanced analyte detection.

Purpose of the Study:

• To propose and analyze a novel high-index core flat fiber plasmonic biosensor.
• To evaluate its performance for refractive index (RI) sensing in the range of 1.53 to 1.60.
• To assess its suitability for biological and organic analyte sensing applications.

Main Methods:

• A high-index (GeO2 doped silica) core flat fiber design was proposed.
• A rectangular analyte channel with TiO2 and gold deposition was fabricated.
• Sensing performance was analyzed at two operating wavelengths.

Main Results:

• The sensor achieved an average wavelength sensitivity of 5000 nm/RIU and a resolution of 2x10^-05 RIU.
• Identical linearity was observed, a rare feature in prior sensors.
• Outstanding detection accuracy (0.01 nm^-1), detection limit (79.28 nm), and figure of merit (50 RIU^-1) were recorded.

Conclusions:

• The proposed flat fiber plasmonic biosensor exhibits excellent sensing performance and linearity.
• Its unique detection range and accuracy make it highly suitable for biological and organic analyte sensing.
• The sensor offers an efficient, flexible, and miniaturized solution for biosensing.