Differential twin receiving fiber-optic magnetic field and electric current sensor utilizing a microfiber coupler

Area of Science:

• Optoelectronics
• Sensor Technology
• Materials Science

Background:

• Accurate measurement of magnetic fields and electric currents is crucial in various scientific and industrial applications.
• Existing sensors may face limitations in sensitivity, size, or cross-interference.
• Microfiber couplers offer unique optical properties suitable for sensitive detection.

Purpose of the Study:

• To propose and demonstrate a novel sensor for simultaneous measurement of magnetic fields and electric currents.
• To investigate the sensor's performance based on microfiber coupler technology.
• To achieve high sensitivity and eliminate cross-sensitivity variations.

Main Methods:

• Fabrication of a sensor by integrating a microfiber coupler (MC) with an aluminum (Al) wire.
• Utilizing the Lorentz force effect on the Al wire for magnetic field detection.
• Exploiting the thermal expansion of the Al wire due to electric current for current sensing.
• Analyzing the ratio of output signal differences to sums for sensitivity normalization.

Main Results:

• The sensor demonstrated a magnetic field sensitivity of approximately 0.0496 mT⁻¹.
• The sensor achieved an electric current sensitivity of approximately 1.0899 A⁻¹ in the absence of a magnetic field.
• The proposed method effectively eliminated variations in sensitivity by using the ratio of output signals.
• The sensor exhibited good repeatability in measurements.

Conclusions:

• A differential twin receiving microfiber coupler sensor is effective for measuring magnetic fields and electric currents.
• The sensor design offers high sensitivity and a method to mitigate cross-sensitivity.
• This technology presents a promising approach for developing advanced electrical sensing devices.