Related Experiment Video
Updated: Jun 3, 2026

A Random-displacement Measurement by Combining a Magnetic Scale and Two Fiber Bragg Gratings
Published on: September 30, 2019
Characteristics of the dual-bridge giant magnetoresistance magnetometer
1Institute of Mechanical and Precision Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 80778, Taiwan. jtjeng@cc.kuas.edu.tw
Abstract:
The responsivity and the field noise characteristics of the giant magnetoresistance (GMR) magnetometer driven by an alternating magnetic field are investigated. The harmonic spectrum of the sensor voltage shows that only the odd harmonics of excitation frequency are sensitive to the external dc field. To cancel out the even harmonics, the dual-bridge GMR magnetometer with the balanced output is proposed. With the dual-bridge configuration, the field-to-voltage transfer coefficient is doubled and the field noise is reduced by a factor of 1.4. The minimum field noise is 7 nT∕√Hz at 1 Hz with the ac excitation power of 5.5 mW. The proposed sensor is suitable for the electronic compass application.
Related Concept Videos
Diamagnetism
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets.
Galvanometer
The galvanometer consists of two concave-shaped permanent magnets, providing a uniform radial magnetic field in the annular region. In the center, a pivoted coil of fine copper wire is placed in the uniform magnetic...
Ferromagnetism
Magnetic Susceptibility and Permeability
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
Other Unique Bacteria
Magnetism
An individual magnetic pole cannot be isolated. No matter how small, every piece of a magnet contains a north pole and a south...

