Engineering and controlling topological spin textures for use in practical applications

Magnetic skyrmions, common swirling physiographic defects in topological spin textures, behave as particles that can potentially be manipulated for use in communications technology. However, their typically large diameter (over 100 nm) limits the skyrmions’ usefulness in information storage and logic applications.

Using first-principles calculations and micromagnetic simulations, researchers have proposed magnetically-stable Janus particles, specifically MnBi₂(Se, Te)_4, to tune a variety of topological magnetic structures in two-dimensional systems.

These results indicate the potential of two-dimensional materials, especially those based on magnetic topological insulating structures, in generating and modulating topological spin textures.

“By using [Van der Waals] heterostructure engineering, magnetic anisotropy in MnBi₂(Se, Te)₄ can be tailored effectively, thereby spontaneously forming sub-10 nm skyrmions in the absence of external [magnetic] fields,” said project author Jiawei Jiang,

According to Jiang, the practical application of skyrmions depends on three key factors: the absence of applied magnetic fields, a size of 10 nm or less, and room temperature conditions.

Because the low Curie temperature is a common problem with most two-dimensional magnetic materials, the researchers believe their current work, which focused on two of the key factors, will stimulate more research efforts towards the development of topologically robust, rewritable magnetic memory.

“Our next topic is to study how to stabilize room-temperature skyrmions from the perspective of theoretical calculations, so as to lead [to] the experimental work,” said Jiang.

Source: “Topological spin textures in a two-dimensional MnBi₂(Se, Te)₄ janus material,” by Jiawei Jiang, Xiang Liu, Rui Li, and Wenbo Mi, Applied Physics Letters (2021). The article can be accessed at https://doi.org/10.1063/5.0057794 .