High-sensitivity temperature sensor using the ultrahigh order mode-enhanced Goos-Hänchen effect.

Area of Science:

• Optoelectronics
• Waveguide Optics
• Sensor Technology

Background:

• The Goos-Hänchen effect describes the lateral displacement of a reflected light beam.
• Metal-cladding waveguides offer unique optical properties for sensing applications.
• Thermo-optic and thermal expansion effects influence waveguide characteristics with temperature changes.

Purpose of the Study:

• To theoretically propose and experimentally demonstrate a high-sensitivity temperature sensor.
• To leverage the enhanced Goos-Hänchen effect in a symmetrical metal-cladding waveguide for temperature sensing.
• To investigate the sensor's performance regarding linearity, resolution, and stability.

Main Methods:

• Theoretical modeling of the enhanced Goos-Hänchen effect in a symmetrical metal-cladding waveguide.
• Experimental setup to measure Goos-Hänchen shifts under varying temperatures (50.0 °C to 51.2 °C).
• Utilizing ultrahigh-order modes for enhanced sensitivity to refractive index and thickness variations.

Main Results:

• Demonstrated a high-sensitivity temperature sensor with a resolution of approximately 5×10(-3) °C.
• Observed good linearity in the sensor's response across the tested temperature range.
• The transduction scheme proved insensitive to light source fluctuations, simplifying practical implementation.

Conclusions:

• The proposed sensor based on the enhanced Goos-Hänchen effect offers a robust and highly sensitive method for temperature measurement.
• The use of ultrahigh-order modes significantly amplifies the detectable changes in waveguide properties.
• This approach provides a practical, high-resolution temperature sensing solution without complex optical instrumentation.