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

Abstract

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 with 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.The electric field (EF) induced spintronic phenomena could offer great benefits to the information-related industries, since they can be harnessed for building information processing devices with ultralow power consumption 1, 2 . Especially, the modification of magnetic parameters, such as the magnetic anisotropy 3-7 , plays an essential role in realizing magnetization switching 5, 8-12 , domain structure modification [13][14][15] , and domain wall motion [16][17][18][19][20][21] . Additionally, recent experiments on magnetic asymmetric multilayers show that the antisymmetric Dzyaloshinskii-Moriya interaction (DMI), which can be induced at the ferromagnet/heavy metal interface [22][23][24][25][26] , is able to further stabilize novel topological spin textures including chiral domain walls, skyrmions, and skyrmion bubbles. In a general context, the skyrmion bubble stands for the topologically non-trivial bubble with a fixed chirality but a larger size in compared with the compact skyrmion 24-26 . These topological spin textures also provide emerging opportunities for developing low-power information processing as well as high-density storage and logic computing technologies 22-29 , which have been theoretically predicted and experimentally demonstrated in the last decade [22][23][24][25]27 .

Noncollinear spintronics and electric-field control: a review

“…Moreover, Ma et al [45] reported that the electric field could tune the creation and motion direction of skyrmion bubbles at room temperature (Fig. 12b), which is of great significance to the ultralow-energy-consumption devices based on skyrmions.…”

Generation and Hall effect of skyrmions enabled using nonmagnetic point contacts

“…The generation of magnetic skyrmions has recently been demonstrated by applying magnetic fields 10 , spin-polarized currents 27,32 , local heating 33 , laser beams 34,35 and electric voltage 36,37 . Meanwhile, skyrmions can also be generated in geometrical constricted devices 6,[38][39][40][41][42] by applying electrical currents 43 .…”

Electric-field-driven non-volatile multi-state switching of individual skyrmions in a multiferroic heterostructure

“…Moreover, the use of EF scheme can avoid the unexpected displacement of skyrmions during the writing process 26 . These features are of great significance to practical applications and have thus promoted the usage of electric field instead of current to manipulate skyrmions 21,22,[26][27][28][29][30][31][32][33] .…”

“…Despite recognition of the potential for the EF manipulation of skyrmions, experimental realizations are limited 21,22,[26][27][28][29] , especially at room temperature [27][28][29] . Room-temperature EF-induced switching of skyrmions was first experimentally realized in the ferromagnet/oxide heterostructures, where the external electric field was directly applied at the ferromagnet/oxide interface to induce an interfacial charge re-distribution.…”