Electric Field-Induced Creation and Directional Motion of Domain Walls and Skyrmion Bubbles

Magnetization
dynamics driven by an electric field could provide
long-term benefits to information technologies because of its ultralow
power consumption. Meanwhile, the Dzyaloshinskii-Moriya interaction
in interfacially asymmetric multilayers consisting of ferromagnetic
and heavy-metal layers can stabilize topological spin textures, such
as chiral domain walls, skyrmions, and skyrmion bubbles. These topological
spin textures can be controlled by an electric field and hold promise
for building advanced spintronic devices. Here, we present an experimental
and numerical study on the electric field-induced creation and directional
motion of topological spin textures in magnetic multilayer films and
racetracks with thickness gradient and interfacial Dzyaloshinskii-Moriya
interaction at room temperature. We find that the electric field-induced
directional motion of chiral domain wall is accompanied by the creation
of skyrmion bubbles at certain conditions. We also demonstrate that
the electric field variation can induce motion of skyrmion bubbles.
Our findings may provide opportunities for developing skyrmion-based
devices with ultralow power consumption.