Voltage-induced Villari effect and hierarchical magnetization states in a ferroelectric-integrated metallic superlattice with perpendicular magnetic anisotropy

Abstract Considerable effort has been devoted to the design of artificial magnetoelectric (ME) materials to address the challenges of high power consumption and switching reliability in spintronic devices. However, special attention must be paid to enhance the required efficiency in terms of achieving a large ME coefficient, non-volatility and 180° switching. In this work, we demonstrate voltage-controlled, nonvolatile, hierarchical and 180° switching of a perpendicularly magnetized [Cu/Ni] superlattice integrated with a ferroelectric [Pb(Mg _1/3 Nb _2/3 )O ₃ ] _0.7 –[PbTiO ₃ ] _0.3 (PMN-PT). A large value of the converse ME coefficient ( α = 1.8 × 10 ⁻⁶ s m ⁻¹ ) associated with 180° switching of the perpendicular magnetic anisotropy is reported here. Distinct voltage induced polarization switching and associated lattice strain in the PMN-PT play an important role in the transient switching process of the perpendicular magnetization of the Ni layers. The obtained results, in particular the voltage induced nonvolatile switching and hierarchical magnetic states in the perpendicularly magnetized system will facilitate the applications of nonvolatile and energy-efficient next-generation information processing devices including neuromorphic computing.