Numerical Study of Graphene/Au/SiC Waveguide-Based Surface Plasmon Resonance Sensor

Area of Science:

• Optoelectronics
• Nanotechnology
• Biosensing

Background:

• Surface Plasmon Resonance (SPR) sensors are crucial for real-time biomolecular interaction analysis.
• Existing SPR sensors face limitations in sensitivity and operational wavelength range.
• Graphene's unique properties offer potential for enhancing SPR sensor performance.

Purpose of the Study:

• To propose and numerically investigate a new waveguide-based SPR sensor incorporating graphene.
• To optimize the sensor design for improved sensitivity and broader operational wavelengths.
• To evaluate the sensor's potential for various biosensing applications.

Main Methods:

• Numerical simulation of a waveguide SPR sensor comprising graphene, gold (Au), and silicon carbide (SiC) layers.
• Characterization by analyzing the shift in resonance wavelength peak with changes in refractive index (RI).
• Comparison of sensor performance with varying numbers of graphene layers.

Main Results:

• The proposed sensor operates in the visible and near-infrared ranges due to SiC's large bandgap energy.
• Increased graphene layers significantly improved sensitivity in the RI range of 1.33–1.36.
• A sensitivity of 2810 nm/RIU was achieved with 10 graphene layers, a 39.1% improvement over sensors without graphene.

Conclusions:

• The graphene/Au/SiC waveguide SPR sensor demonstrates enhanced sensitivity and performance.
• The sensor shows significant promise for portable biosensing in detecting water contaminants, viruses (HBV), glucose, and blood components.
• This technology could advance human health diagnostics and environmental monitoring.