High-temperature sensor based on an abrupt-taper Michelson interferometer in single-mode fiber

Area of Science:

• Optoelectronics
• Fiber optic sensors
• Interferometry

Background:

• Accurate high-temperature sensing is critical in various industrial applications.
• Existing sensors often suffer from cross-sensitivity to environmental factors like refractive index.
• Fiber optic interferometers offer potential for robust sensing solutions.

Purpose of the Study:

• To propose and demonstrate a novel abrupt fiber-taper Michelson interferometer (FTMI) for high-temperature measurement.
• To evaluate the sensor's temperature sensitivity and its cross-sensitivity to refractive index.
• To validate the FTMI's suitability for high-temperature sensing applications.

Main Methods:

• Fabrication of the FTMI using a single-mode fiber, fiber-taper machine, and electric-arc discharge.
• Experimental setup for measuring temperature and refractive index (RI) variations.
• Analysis of wavelength shifts in response to temperature and RI changes.

Main Results:

• Achieved a high temperature sensitivity of 118.6 pm/°C in the 500°C-800°C range.
• Demonstrated minimal wavelength variation (-0.335 nm) with external RI changes from 1.333 to 1.3902.
• Confirmed the sensor's low cross-sensitivity to RI, making it suitable for high-temperature environments.

Conclusions:

• The proposed abrupt FTMI is an effective sensor for high-temperature measurements.
• The sensor exhibits excellent temperature sensitivity and negligible RI cross-sensitivity.
• This technology holds promise for reliable temperature monitoring in demanding conditions.