Wide range voltage-impulse-controlled nonvolatile magnetic memory in magnetoelectric heterostructure

Abstract

The voltage impulse-induced large, nonvolatile, and tunable magnetization switching in a Ni80Co20/Pb(Mg, Nb)O3-PbTiO3 (PMN-PT) structure was investigated at room temperature. Ni80Co20 was deposited onto a specified PMN-PT substrate with defect dipoles. By exploiting defect dipoles, a distinct and stable strain memory state was achieved at zero electric field. It induces and sustains two distinct magnetization states when removing an electric field via the magnetoelectric coupling effect. Via the detailed x-ray diffraction and piezoresponse force microscopy analyses, the polarization switching pathway and the lattice strain in response to the in situ electric field were investigated to understand the microscopic mechanisms behind the nonvolatile magnetic memory. Furthermore, the impulse electric field can be selected in the range between the coercive field and the saturation field of the PMN-PT, leading to a wide range controlling technique. This work provides a promising way to produce a large and nonvolatile magnetic memory in magnetoelectric heterostructure and is significant for ultra-low-power information storage devices.