The skyrmion bags in an anisotropy gradient

Abstract

Skyrmion bags as spin textures with arbitrary topological charge are expected to be the carriers in racetrack memory. Here, we theoretically and numerically investigated the dynamics of skyrmion bags in an anisotropy gradient. It is found that, without the boundary potential, the dynamics of skyrmion bags are dependent on the spin textures, and the velocity of skyrmionium with $Q=0$ is faster than other skyrmion bags. However, when the skyrmion bags move along the boundary, the velocities of all skyrmion bags with different $Q$ are same. This can be attributed to the same value of $u/{\eta }_{xx}$, where the $u$ and ${\eta }_{xx}$ are the terms related to the magnetization distribution of skyrmion bag. In addition, we theoretically derived the dynamics of skyrmion bags in the two cases using the Thiele approach and discussed the scope of Thiele equation. Within a certain range, the simulation results are in good agreement with the analytically calculated results. Our findings provide an alternative way to manipulate the racetrack memory based on the skyrmion bags.

7 pages, 5 figures, 2 tables

References in corpus (9)

• Magnetic skyrmion logic gates: conversion, duplication and merging of skyrmions
• Theory of current-driven motion of Skyrmions and spirals in helical magnets
• Skyrmion-skyrmion and skyrmion-edge repulsions in skyrmion-based racetrack memory
• Thermally Driven Ratchet Motion of Skyrmion Microcrystal and Topological Magnon Hall Effect
• Magnetic skyrmion-based synaptic devices
• Magnetic Skyrmion Bundles and Their Current-Driven Dynamics
• Geometry and Symmetry in Skyrmion Dynamics
• Ultrafast domain wall motion in ferrimagnets induced by magnetic anisotropy gradient
• Magnetic skyrmion binning

Cited by in corpus (3)

• Embedded skyrmion bags in thin films of chiral magnets
• Controllable Creation of Skyrmion Bags in a Ferromagnetic Nanodisk
• Global Rotation of Skyrmion Bags under Vertical Microwave Fields