Electric-field control of skyrmions in multiferroic heterostructure via magnetoelectric coupling

Abstract

Room-temperature skyrmions in magnetic multilayers are considered to be promising candidates for the next-generation spintronic devices. Several approaches have been developed to control skyrmions, but they either cause significant heat dissipation or require ultrahigh electric fields near the breakdown threshold. Here, we demonstrate electric-field control of skyrmions through strain-mediated magnetoelectric coupling in ferromagnetic/ferroelectric multiferroic heterostructures. We show the process of non-volatile creation of multiple skyrmions, reversible deformation and annihilation of a single skyrmion by performing magnetic force microscopy with in situ electric fields. Strain-induced changes in perpendicular magnetic anisotropy and interfacial Dzyaloshinskii–Moriya interaction strength are characterized experimentally. These experimental results, together with micromagnetic simulations, demonstrate that strain-mediated magnetoelectric coupling (via strain-induced changes in both the perpendicular magnetic anisotropy and interfacial Dzyaloshinskii–Moriya interaction is responsible for the observed electric-field control of skyrmions. Our work provides a platform to investigate electric-field control of skyrmions in multiferroic heterostructures and paves the way towards more energy-efficient skyrmion-based spintronics.

Engineering Co Vacancies for Tuning Electrical Properties of p-Type Semiconducting Co3O4 Films

“…The energy cutoff was 500 eV. According to Perdew–Burke–Ernzerhof, the exchange–correlation potential was treated by generalized gradient approximation, and the onsite Coulomb interaction ( U eff ) of 2.0 was applied for the Co ions. , …”

“…It is interesting to tune the electrical properties of Co 3 O 4 by the ferroelectric field effect. Previously, the carriers of Mn:ZnO, Al:ZnO, Co:SnO 2 , In 2– x Cr x O 3 , and Bi 0.94 Pb 0.06 CuSeO semiconductors could be accumulated and dissipated by the ferroelectric field effect of the Pb­(Mg 1/3 Nb 2/3 ) 0.7 Ti 0.3 O 3 (PMN-PT) substrate, leading to the low- and high-resistance states. − Co 3 O 4 is a p-type semiconductor with Co vacancies as the origin of conductivity, whose electrical properties are sensitive to the structure and morphology. ,,− Here, the PMN-PT substrate is a good choice to modulate the electrical properties of Co 3 O 4 , which has been widely used for mediating the physical properties of two-dimensional materials, , antiferromagnetic materials, single-layer films, , multilayer structures, and magnetic tunnel junctions . On one hand, it possesses a special surface morphology and phase transition based on the ferroelectric characteristic, − which can influence the crystal quality of Co 3 O 4 in the preparation process.…”

Electric-field-assisted non-volatile magnetic switching in a magnetoelectronic hybrid structure

“…2.3 and 2.6 , 2.3 and 2.6 . It is mentionable that the magnetic switching process of the parallel (antiparallel) to antiparallel (parallel) state with the H-field bias is completed through the domain wall formation and propagation under both 0 kV/cm and 6 kV/cm (see Figure S16 in the supplemental information ), resulting in a sharp magnetization reversal in the vicinity of the switching fields ( Czapkiewicz et al., 2004 ; Ba et al, 2021 ). This simulation result is well consistent with our aforementioned experimental observation.…”

Magnetoelectric Memory Based on Ferromagnetic/Ferroelectric Multiferroic Heterostructure

“…Their efforts offer a new strategy for achieving a giant, nonvolatile, and reversible electric-field control of magnetization via strain coupling in the FM/FE heterostructures, which would be employed in the ME memory design. So far, FM/FE heterostructures have become a unique playground, not only for studying the strain-driven electric field manipulation novel physical effects, such as electric-field control of exchange bias [ 82 , 83 ], RKKY interaction [ 84 ], and skyrmions [ 85 , 86 ], but also for exploiting the related ME devices.…”