Vibrational noise rejection in multilayer structured magnetoelectric sensor

Abstract Giant ME effects in laminates have been investigated for highly sensitive low frequency magnetic field sensors. It has been shown in recent years that one of the biggest obstacles for magnetoelectric (ME) sensors achieving high sensitivity at low frequency is the vibrational noise introduced via piezoelectric effect. This work demonstrates a novel differential technique which has the ability to reject the vibrational noise in a multilayer structured ME sensor. It exhibits an excellent ME effect with a low equivalent magnetic noise floor of 32 pT/Hz 1/2 at 1 Hz and 3 pT/Hz 1/2 at 10 Hz, which was very close to the predicted value (27 pT/Hz 1/2 at 1 Hz and 2.9 pT/Hz 1/2 at 10 Hz). With respect to the ability to reject the vibrational noise, the external vibrational noise was incredibly attenuated by 91%. These unique properties of the multilayer structured sensor offer potential applications as a precise and sensitive magnetic field detector.