Real-time and high-sensitivity refractive index sensing with an arched optofluidic waveguide

Area of Science:

• Optofluidics
• Sensor Technology
• Analytical Chemistry

Background:

• Refractive index (RI) sensing is crucial for analytical chemistry, medical diagnosis, and environmental monitoring.
• Optofluidic techniques offer high integration, sensitivity, and low cost for RI sensor design.
• Simultaneous real-time RI measurement with high sensitivity and low detection limit remains a challenge.

Purpose of the Study:

• To design and fabricate a novel optofluidic RI sensor.
• To achieve real-time RI detection with high sensitivity and low detection limit.
• To demonstrate the sensor's versatility across different RI ranges.

Main Methods:

• Fabrication of an arched optofluidic waveguide sensor.
• Monitoring light power loss through the waveguide.
• Numerical simulation and experimental investigation of sensor performance.
• Testing the sensor across a specific RI range (1.333 to 1.392).

Main Results:

• The sensor achieved real-time RI detection with high sensitivity.
• A superior sensitivity exceeding -19.2 mW/RIU was recorded.
• A low detection limit of 5.21×10^-8 RIU was achieved.
• The sensor demonstrated a wide linear dynamic range.

Conclusions:

• The developed arched optofluidic waveguide sensor provides a promising solution for real-time, high-sensitivity RI sensing.
• The sensor's design allows for customization to cover multiple RI ranges for diverse applications.
• This technology advances RI sensing capabilities in analytical and diagnostic fields.