Magnetoelectric surface acoustic wave resonator with ultrahigh magnetic field sensitivity

TL;DR

This paper introduces a magnetoelectric surface acoustic wave resonator capable of detecting extremely weak magnetic fields with ultrahigh sensitivity, leveraging a novel frequency shift detection mechanism in a broadband, bias-free setup.

Contribution

It proposes a new MESAW device based on piezoelectric/magnetostrictive heterostructure that achieves unprecedented magnetic field sensitivity and broadband detection without bias magnetic field.

Findings

Sensitivity up to 10^(-11) Tesla

Operates without bias magnetic field

Broadband detection capability

Abstract

A magnetoelectric surface acoustic wave (MESAW) type device based on piezoelectric/magnetostrictive heterostructure was proposed to use as weak magnetic field sensor. Unlike conventional magnetoelectric bulk laminates or film stacks collecting magnetic field induced electrical charge, the MESAW detects the shift of the center frequency, which highly depends on the magnetic field due to the giant delta E effect and the phase velocity dispersion. The magnetic field sensitivity can reach 10^(-11) Tesla in consideration of 100 Hz frequency accuracy. Additionally, the unique working mechanism of MESAW allows a broadband detection of weak magnetic field even with no bias magnetic field.