Detection of pico-Tesla magnetic fields using magneto-electric sensors at room temperature

Abstract

The measurement of low-frequency (10−2–103Hz) minute magnetic field variations (10−12Tesla) at room temperature in a passive mode of operation would be critically enabling for deployable neurological signal interfacing and magnetic anomaly detection applications. However, there is presently no magnetic field sensor capable of meeting all of these requirements. Here, we present new bimorph and push-pull magneto-electric laminate composites, which incorporate a charge compensation mechanism (or bridge) that dramatically enhances noise rejection, enabling achievement of such requirements.

Electrical tuning of magnetism in Fe3O4/PZN–PT multiferroic heterostructures derived by reactive magnetron sputtering

“…[1][2][3][4][5][6][7][8][9] Multiferroic composites consisting of ferro/ferrimagnetic and ferroelectric phases are widely recognized to be able to realize electric field control of magnetic order due to its strong strain mediated magnetoelectric ͑ME͒ coupling resulting from the inversed piezoelectric effect and piezomagnetic effect. [10][11][12][13][14][15][16][17][18][19] Several multiferroic heterostructures have been known to show large electrical field manipulation of magnetism, such as FeGaB/Si/PMN-PT ͑lead magnesium niobate-lead titanate͒, yttrium iron garnet ͑YIG͒/PMN-PT and YIG/BSTO ͑barium strontium titanate͒, 8,10,11,20,21 which show great prospects for E-field tunable magnetic devices.…”

Enhanced magnetoelectric effect in heterostructure of magnetostrictive alloy bars and piezoelectric single-crystal transformer

“…[1][2][3][4] While the ME effect was first observed in single-phase materials such as Cr 2 O 3 , the inherently weak ME coupling and the complex synthesis process impede the application viability of the materials. [5][6][7][8] By contrast, multiphase laminated composites based on magnetostrictive and piezoelectric materials have resulted in practically useable extrinsic ME effect characterized by large ME voltage coefficients (α V = dV/dH) in excess of 20 mV/Oe over broad ranges of frequency (>20 kHz) and temperature (>60 • C).…”

Enhancement in magnetic field sensitivity and reduction in equivalent magnetic noise by magnetoelectric laminate stacks

“…[1][2][3][4] Based on a giant ME effect, two phase piezoelectric/magnetostrictive laminates have shown the potential for low frequency ( 10 2 Hz), low cost, low power, and room temperature magnetic sensors. [5][6][7] A ME magnetic sensor with a low equivalent magnetic noise and a 10 pT magnetic field sensitivity have recently been reported. 8 A ME sensor with a high signal-to-noise ratio (SNR) requires not only a high value of a ME so as to achieve high output signals but also requires a low equivalent magnetic noise in the absence of an incident field.…”