Strain-controlled magnetic domain wall propagation in hybrid piezoelectric/ferromagnetic structures

TLDR

Controlling magnetic order in nanoscale devices is essential for integrating spintronics into conventional electronics, yet energy‑efficient methods are scarce; magnetoelectric coupling in magnetostrictive/piezoelectric systems offers a promising route, though practical geometries remain underexplored. The study demonstrates that sizeable anisotropy changes can be generated in hybrid piezoelectric/spin‑valve nanowires by applying electric fields to induce strains. These anisotropy changes arise from electric‑field‑driven strain in the piezoelectric layer, which modulates the magnetic anisotropy of the adjacent magnetostrictive spin‑valve. Domain‑wall propagation fields are doubled under locally applied strains, showing that electric‑field control can enable low‑power domain‑wall gates and more efficient magnetic logic devices.

Abstract

The control of magnetic order in nanoscale devices underpins many proposals for integrating spintronics concepts into conventional electronics. A key challenge lies in finding an energy-efficient means of control, as power dissipation remains an important factor limiting future miniaturization of integrated circuits. One promising approach involves magnetoelectric coupling in magnetostrictive/piezoelectric systems, where induced strains can bear directly on the magnetic anisotropy. While such processes have been demonstrated in several multiferroic heterostructures, the incorporation of such complex materials into practical geometries has been lacking. Here we demonstrate the possibility of generating sizeable anisotropy changes, through induced strains driven by applied electric fields, in hybrid piezoelectric/spin-valve nanowires. By combining magneto-optical Kerr effect and magnetoresistance measurements, we show that domain wall propagation fields can be doubled under locally applied strains. These results highlight the prospect of constructing low-power domain wall gates for magnetic logic devices. The use of electric fields to control the magnetization of ferromagnetic materials could enable more efficient electronics. Lei et al.show that by applying lateral strain to a magnetostrictive nanowire with a piezoelectric, voltage-controlled gating of magnetic domain wall motion in the wire can be achieved.