Optimization of a horizontal slot waveguide biosensor to detect DNA hybridization

Area of Science:

• Photonics and Nanotechnology
• Biomedical Engineering
• Materials Science

Background:

• Biosensors are crucial for detecting biological molecules like DNA.
• Waveguide-based sensors offer high sensitivity and miniaturization potential.
• Optimizing waveguide structures enhances sensing performance.

Purpose of the Study:

• To optimize a horizontal slot waveguide biosensor for DNA hybridization detection.
• To analyze key performance parameters including power confinement, power density, and sensitivity.
• To evaluate the biosensor's performance in both Mach-Zehnder and ring resonator configurations.

Main Methods:

• Utilizing a full-vectorial H-field formulation-based finite element approach.
• Optimizing device parameters of the slot waveguide.
• Simulating and analyzing waveguide performance for DNA hybridization detection.

Main Results:

• Key parameters like normalized power confinement, power density, and change in effective index were analyzed.
• A compact 90.0 μm long Mach-Zehnder section was designed for DNA hybridization detection.
• A ring resonator arrangement achieved a high sensitivity of 893.5 nm/RIU.

Conclusions:

• The optimized horizontal slot waveguide biosensor effectively detects DNA hybridization.
• The proposed design demonstrates high sensitivity, suitable for advanced biosensing.
• The finite element method provides an effective tool for biosensor optimization.