Magnetic skyrmions on a two-lane racetrack

Abstract

Magnetic skyrmions are particle-like textures in the magnetization, characterized by a topological winding number. Nanometer-scale skyrmions have been observed at room temperature in magnetic multilayer structures. The combination of small size, topological quantization, and their efficient electric manipulation makes them interesting candidates for information carriers in high-performance memory devices. A skyrmion racetrack memory has been suggested where information is encoded in the distance between skyrmions moving in a one-dimensional nanostrip. Here, we propose an alternative design where skyrmions move in two (or more) parallel lanes and the information is stored in the lane number of each skyrmion. Such a multilane track can be constructed by controlling the height profile of the nanostrip. Repulsive skyrmion-skyrmion interactions in narrow nanostrips guarantee that skyrmions on different lanes cannot pass each other. Current pulses can be used to induce a lane change. Combining these elements provides a robust, efficient design of skyrmion-based storage devices.

Manipulating and trapping skyrmions by magnetic field gradients

“…Different from the case of an isolated skyrmion, a collision effect among the skyrmions will occur, but the particle-like skyrmions cannot be fused together due to the repulsive interaction between them. As a result, a stable hexagonal distribution is eventually formed for these skyrmions, see figures 5(a)-(f) [44]. The separation between two skyrmions is determined by the competition between the repulsive force and the driving force from the gradient field [45].…”

Interplay between size and stability of magnetic skyrmions

“…The interest in skyrmions is motivated by their unique properties potentially making them perfect information carriers [4][5][6][7]. Sensitivity of these spin swirls to pulses of electric current [8][9][10] benefits the efficient control of information flows and facilitates qualitative decrease in power consumption of data processing devices.…”

Quantification of Magnetic Surface and Edge States in an FeGe Nanostripe by Off-Axis Electron Holography

“…An observed difference in measured saturation magnetization between helices and Skyrmions was attributed to the 3D nature of the Skyrmion model, which involved chiral surface twists. Such magnetic boundary states are important for the exploitation of Skyrmion-based devices, as they affect the particlelike properties of topologically protected spin textures and are likely to have a strong effect on magnetotransport properties [8,34,38] and spin wave excitations [39] in chiral magnet nanostructures. From a methodological perspective, the experimental approach that we use opens new avenues for exploring quantum confinement in other complex noncollinear spin systems at the nanoscale.…”