Abstract
Control of magnetic domain-wall motion by electric fields has recently attracted scientific attention because of its potential for magnetic logic and memory devices. Here, we report on a new driving mechanism that allows for magnetic domain-wall motion in an applied electric field without the concurrent use of a magnetic field or spin-polarized electric current. The mechanism is based on elastic coupling between magnetic and ferroelectric domain walls in multiferroic heterostructures. Pure electric-field-driven magnetic domain-wall motion is demonstrated for epitaxial Fe films on BaTiO3 with in-plane and out-of-plane polarized domains. In this system, magnetic domain-wall motion is fully reversible and the velocity of the walls varies exponentially as a function of out-of-plane electric-field strength.Received 22 August 2014DOI:https://doi.org/10.1103/PhysRevX.5.011010This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.Published by the American Physical Society
Highlights
Domain walls in ferromagnetic thin films or nanowires are conventionally driven by magnetic fields or spinpolarized electric currents [1,2,3,4,5,6,7,8,9,10]
The magnetic domain walls are driven by a magnetic field or electric current and the velocity of the walls is altered by an electric-field effect on the magnetic anisotropy
Rotation of the polarization at the domain boundaries coincides with an abrupt change of the BaTiO3 in-plane lattice structure: The unit cell of a domains in the (001)-oriented surface is rectangular with a tetragonality of 1.1%, and the in-plane lattice of c domains is cubic
Summary
Domain walls in ferromagnetic thin films or nanowires are conventionally driven by magnetic fields or spinpolarized electric currents [1,2,3,4,5,6,7,8,9,10]. In the thermally activated creep regime, domain-wall motion depends sensitively on the disorder-induced pinning energy barrier and the depinning field [12] This notion has led to various demonstrations of electric-field control over the pinning strength and velocity of magnetic domain walls via voltage-induced changes of magnetic anisotropy. Multiferroic heterostructures with lateral anisotropy modulations are characterized by strong pinning of magnetic domain walls onto narrow ferroelectric domain boundaries [37]. This robust coupling effect forces the magnetic domain walls to follow their ferroelectric counterparts when the latter are displaced in an applied electric field, providing a new way to drive magnetic domain walls by pure electrical means. The spin structure and strong elastic pinning of such domain walls to a-c boundaries are sustained up to high driving velocities
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
