Enhanced dc magnetic field sensitivity by improved flux concentration in magnetoelectric laminates

In this letter, we present magnetostatic modeling results that show significant magnetic field concentration tunability through geometric modification of high-mu tnagnetostatic Metglas layers of laminate magnetoelectric (ME) sensors. Based on the modeling results, composite ME sensors were fabricated with longer Metglas foils and found to exhibit notably higher ME voltage coefficients at smaller DC magnetic biases in response to a 1 kHz driving signal. Such ME sensors have been used to detect DC magnetic field changes as small as 6 nT at 1 kHz, while maintaining a signal-to-noise ratio greater than 10. This represents an enhancement of similar to 250% relative to values previously reported for Metglas/Pb(Zr,Ti)O(3) laminates. (C) 2011 American Institute of Physics. [doi:10.1063/1.3650713]