# A Portable Magnetoelectric Gaussmeter Based on Torque Effect

## TL;DR

A portable gaussmeter using torque effect can detect both DC and AC magnetic fields, offering high sensitivity and low cost for practical applications.

## Contribution

A portable magnetoelectric gaussmeter capable of detecting both DC and AC magnetic fields is developed using the torque effect.

## Key findings

- The gaussmeter has a detection range of 0~10 Oe and can operate from DC to 500 Hz.
- The device achieves an AC detection limit of 0.01 Oe and a DC detection limit of 0.08 Oe.
- The system is powered by a 5V 2A adapter or battery, making it pocket-sized and highly portable.

## 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.