Related Experiment Video
Updated: Mar 10, 2026
07:28
Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor
Published on: August 30, 2012
11.2K
Mid-IR absorption sensing of heavy water using a silicon-on-sapphire waveguide
Optics Letters
|December 16, 2016
Summary
A new silicon-on-sapphire waveguide sensor enables mid-infrared absorption spectroscopy for sensitive gas and liquid detection. It accurately measures heavy water concentrations, with potential uses in body fat analysis and nuclear reactor safety.
Area of Science:
- Photonics and Spectroscopy
- Materials Science
- Chemical Sensing
Background:
- Conventional infrared transmission techniques struggle with highly absorptive liquids and chemically similar molecules.
- Compact, sensitive sensors are needed for real-time chemical analysis in diverse applications.
Purpose of the Study:
- To demonstrate a compact silicon-on-sapphire (SOS) strip waveguide sensor for mid-infrared (mid-IR) absorption spectroscopy.
- To showcase its capability for precise detection of chemically similar molecules and highly absorptive liquids.
- To validate its performance by measuring low concentrations of heavy water (D2O).
Main Methods:
- Fabrication of a silicon-on-sapphire (SOS) strip waveguide.
- Utilizing mid-IR absorption spectroscopy for chemical sensing.
- Testing the sensor's sensitivity with D2O-H2O mixtures at the 4 μm absorption band.
Main Results:
- Successfully demonstrated a compact SOS strip waveguide sensor for mid-IR absorption spectroscopy.
- Reliably measured concentrations as low as 0.25% of D2O in a D2O-H2O mixture.
- The sensor shows high sensitivity at the D2O absorption band around 4 μm.
Conclusions:
- The developed SOS waveguide sensor is effective for mid-IR absorption spectroscopy.
- This CMOS-compatible sensor offers a promising platform for sensitive gas and liquid detection.
- Potential applications include body fat measurement and nuclear reactor coolant leak detection.
