Frequency tunable resonant magnetoelectric sensors for the detection of weak magnetic field

This paper reports on frequency tunable MEMS magnetoelectric (ME) sensors. Different designs are studied in respect to ME voltage coefficient and frequency tunability. Compared to state-of-the-art ME sensors, the presented ME resonators display a highly reversible and linear frequency tuning, enabled by applying a DC voltage to piezoelectric actuators. A frequency shift of up to 0.2 Hz V-1 is demonstrated for a sensor with a limit of detection of 128 pT/Hz(0.5) at resonance frequency of 13 kHz. This sensor type is of particular interest for vector field sensors and sensor arrays in bio-magnetic applications, where sensors with either identical resonance frequencies or precisely defined frequency spacing are required.