A hexagonal-framed magnetoelectric composite for magnetic vector measurement

In this work, a multi-terminal hexagonal-framed magnetoelectric composite (HFMEC) made of amorphous FeBSi alloy (Metglas) ribbons and three sandwiched [011]-oriented PMN-PT single-crystal fibers (Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃) arranged with a 120° interval is presented, and the directional magnetoelectric (ME) effect of the HFMEC operating in the L-T mode under a constant-amplitude AC magnetic field is investigated. It is found that the HFMEC exhibits threefold symmetric directional ME coupling in response to an applied in-plane DC magnetic field H_DC, while each ME terminal shows a twofold symmetry due to the magnetization and demagnetization effect of H_DC. Moreover, a valid formula for calculating the angular direction of the magnetic field is also presented. It is further revealed that the HFMEC exhibits a "V" shaped ME voltage output as a response to H_DC due to the geomagnetic field (H_Geo) effect, and the knee point of the curve literally reveals the magnitude of local H_Geo, while the direction of H_DC indicates a reverse direction of H_Geo. The proposed HFMEC provides a great potential for a vector magnetometer as well as geomagnetic sensor application.