Electric-field control of non-volatile magnetization switching without external-magnetic-field bias in CoFeB/(011)-PMN-0.3PT heterostructures

Electric-field control of non-volatile magnetization switching in the absence of external-magnetic-field bias has been investigated in multiferroic Co40Fe40B20/0.7Pb(Mg1/3Nb2/3)-0.3PbTiO3 (CoFeB/PMN-0.3PT) heterostructure at room temperature. The two non-volatile magnetic states are achieved without magnetic-field bias and can be switched in a reversible and reproducible manner by an electric field. These results are attributed to the modulation of the magnetic anisotropy of the CoFeB layer by as-grown magnetic field and electric-field-induced non-volatile strain through unipolar-electric-field cycling. High-resolution X-ray diffraction studies on the (022) peaks under in situ electric field indicate that the non-volatile strain is closely related to the 71° ferroelastic domain switching ( to ) of the PMN-0.3PT substrate. The corresponding ratio of the ferroelastic domain is electrically changed by 14.1% between the two non-volatile magnetic states. Our results provide a promising path to non-magnetically operating magnetic bits by pure electric field at room temperature.