An Extremely Low Equivalent Magnetic Noise Magnetoelectric Sensor

Extremely low equivalent magnetic noise in a Metglas/piezofiber magnetoelectric (ME) magetic-field sensor, realized through a combination of a giant ME effect and a reduction in constituent internal noise sources, is demonstrated. The ME coefficient is 52 V cm−1 Oe−1 at low frequency, the 1 Hz equivalent magnetic noise is 5.1 pT Hz−1/2, and the magnetic field sensitivity is 10 nT.