Low-temperature cross-talk magnetic-field sensor based on tapered all-solid waveguide-array fiber and magnetic...

Area of Science:

• Photonics and Sensor Technology
• Materials Science
• Magnetism

Background:

• Accurate magnetic field measurement is crucial in various scientific and industrial applications.
• Existing sensors can suffer from temperature cross-sensitivity, limiting their precision.
• Fiber-optic sensors offer advantages in remote and harsh environment sensing.

Purpose of the Study:

• To propose and experimentally demonstrate a compact fiber-optic magnetic-field sensor.
• To investigate the sensor's performance in terms of sensitivity and temperature cross-sensitivity.
• To leverage the properties of all-solid waveguide-array fiber (WAF) and magnetic fluid (MF).

Main Methods:

• Fabrication of a tapered all-solid WAF using a fusion splicer.
• Assembly of the sensor by immersing the tapered WAF into magnetic fluid (MF).
• Measurement and analysis of transmission spectra under varying magnetic field intensities and temperatures.

Main Results:

• Achieved a magnetic-field sensitivity of 44.57 pm/Oe within a linear range of 50-200 Oe.
• Demonstrated low temperature-induced wavelength shift perturbation (<0.3 nm) over a temperature range of 26.9°C-44°C.
• Confirmed that magnetically induced refractive-index changes in MF are significantly larger than thermally induced changes.

Conclusions:

• The proposed fiber-optic magnetic-field sensor based on tapered WAF and MF offers high sensitivity and low temperature cross-sensitivity.
• The sensor's simple structure and ease of fabrication are significant advantages.
• This technology is promising for reducing temperature cross-sensitivity in magnetic field measurements.