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Updated: May 28, 2025

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
A Portable Magnetoelectric Gaussmeter Based on Torque Effect
Jingen Wu1, Jiacheng Qiao1, Xianfeng Liang2
1State Key Laboratory for Manufacturing Systems Engineering, Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Engineering Research Center of Spin Quantum Sensor Chips, Universities of Shaanxi Province, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Abstract:
A giant magnetoelectric coefficient has been discovered in laminated magnetoelectric composites incorporating piezoelectric and magnetostrictive layers, which reveals a high sensitivity in AC magnetic field detection under a DC bias field. However, the DC-biased magnetoelectric composites are not capable of detecting DC magnetic fields due to the interference with the DC signal to be measured. Here, we demonstrate a portable magnetoelectric gaussmeter based on torque effect that can detect both DC and AC magnetic fields. The proposed gaussmeter is equipped with a magnetoelectric sensor, a charge amplification module, a signal processing circuit, a power module, a data processing program, a display module, etc. The proposed gaussmeter indicates such performance indexes as an intensity range of 0~10 Oe, frequency range of DC~500 Hz, AC detection limit of 0.01 Oe, DC detection limit of 0.08 Oe, and frequency resolution of 1 Hz. Being powered by a power adapter (or a battery) of 5V 2A, the whole device system is pocket-size, low-cost, and highly portable, demonstrating its potential for magnetic field detection as a distributed sensor.
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