AC/DC dual-mode magnetoelectric sensor with high magnetic field resolution and broad operating bandwidth

In this study, a dual-mode Metglas/Pb(Zr,Ti)O-3 magnetoelectric (ME) sensor was prepared for measuring weak magnetic fields. It is interesting to note that this ME sensor can work at alternating current (AC) and direct current (DC) dual-modes with high field resolution. In AC mode, a very accurate AC magnetic field resolution of 0.8 nT was achieved at a mechanical resonance frequency of 72.2 kHz; moreover, the operating frequency band for resolution better than 1 nT is as wide as 3.4 kHz. We proposed a DC bias field perturbation (DBFP) method to detect the DC magnetic field using lock-in amplifier technology. As a result, an ultra-accurate DC field resolution of 0.9 nT with noise power spectral density as low as 100 pT/root Hz was obtained in the studied ME sensor via the DBFP method. The dual-mode ME sensor enables simultaneous measurement for DC and AC magnetic fields with wideband and accurate field resolution, which greatly enhances the measurement flexibility and application scope.

Automated summary

In this study, a dual-mode Metglas/Pb(Zr,Ti)O-3 magnetoelectric sensor was developed for measuring weak magnetic fields in both AC and DC modes with high resolution. The sensor achieved accurate AC magnetic field resolution of 0.8 nT at a wide operating frequency range, and a ultra-accurate DC magnetic field resolution of 0.9 nT with low noise power spectral density using the DBFP method. The dual-mode sensor enhances measurement flexibility and application scope for simultaneous wideband measurement of DC and AC magnetic fields.