Broad-band difference interferometer as a refractive index sensor

Area of Science:

• Integrated optics
• Optical sensing
• Interferometry

Background:

• Existing integrated optical label-free affinity sensors can be costly.
• There is a need for economical and miniaturized sensing technologies.

Purpose of the Study:

• Introduce the Integrated Optical Broad-Band Difference Interferometer (IO BB DI) as a cost-effective alternative.
• Analyze the theoretical performance and operational parameters of the IO BB DI.
• Investigate the impact of waveguide layers on sensor performance.

Main Methods:

• Detailed theoretical analysis of the IO BB DI principle.
• Modeling the influence of Si3N4/SiO2 waveguide layers.
• Evaluating the interferometer's performance with a short operating distance (<0.5 mm).

Main Results:

• The IO BB DI demonstrates potential as an economical label-free affinity sensor.
• Waveguide layer properties significantly affect the interferometer's operation.
• A short operating distance (<0.5 mm) facilitates device miniaturization.

Conclusions:

• The IO BB DI is a viable and economical alternative for integrated optical label-free affinity sensing.
• The technology leverages standard microelectronic fabrication processes (Si3N4/SiO2).
• Miniaturization is achievable due to the interferometer's short operating distance.