65 research outputs found
Interface engineering of domain structures in BiFeO3 thin films
A wealth of fascinating phenomena have been discovered at the BiFeO3 domain walls, examples such as domain wall conductivity, photovoltaic effects, and magnetoelectric coupling. Thus, the ability to precisely control the domain structures and accurately study their switching behaviors is critical to realize the next generation of novel devices based on domain wall functionalities. In this work, the introduction of a dielectric layer leads to the tunability of the depolarization field both in the multilayers and superlattices, which provides a novel approach to control the domain patterns of BiFeO3 films. Moreover, we are able to study the switching behavior of the first time obtained periodic 109° stripe domains with a thick bottom electrode. Besides, the precise controlling of pure 71° and 109° periodic stripe domain walls enable us to make a clear demonstration that the exchange bias in the ferromagnet/BiFeO3 system originates from 109° domain walls. Our findings provide future directions to study the room temperature electric field control of exchange bias and open a new pathway to explore the room temperature multiferroic vortices in the BiFeO3 system
Electric-field-driven Non-volatile Multi-state Switching of Individual Skyrmions in a Multiferroic Heterostructure
Electrical manipulation of skyrmions attracts considerable attention for its
rich physics and promising applications. To date, such a manipulation is
realized mainly via spin-polarized current based on spin-transfer torque or
spin-orbital torque effect. However, this scheme is energy-consuming and may
produce massive Joule heating. To reduce energy dissipation and risk of
heightened temperatures of skyrmion-based devices, an effective solution is to
use electric field instead of current as stimulus. Here, we realize an
electric-field manipulation of skyrmions in a nanostructured
ferromagnetic/ferroelectrical heterostructure at room temperature via an
inverse magneto-mechanical effect. Intriguingly, such a manipulation is
non-volatile and exhibits a multi-state feature. Numerical simulations indicate
that the electric-field manipulation of skyrmions originates from
strain-mediated modification of effective magnetic anisotropy and
Dzyaloshinskii-Moriya interaction. Our results open a direction for
constructing low-energy-dissipation, non-volatile, and multi-state
skyrmion-based spintronic devices.Comment: Accepted by Nature Communications 11, 3577 (2020
- …