Tuneable skyrmion and anti-skyrmion fluids via mechanical strain in chiral kagome lattice

TL;DR

This study demonstrates how uniaxial mechanical strain can control the stability, density, and topological charge of skyrmions and antiskyrmions in a kagome lattice, offering a new method for engineering spin textures in spintronics.

Contribution

The paper introduces the effect of mechanical strain on skyrmion and antiskyrmion phases in a kagome lattice, revealing tunable topological properties and phase transitions.

Findings

Strain extends skyrmion stability to higher temperatures.

Tensile strain can convert skyrmions into antiskyrmions.

Mechanical deformation alters phase stability and magnetic states.

Abstract

Magnetic skyrmions are nanometric swirling spin textures that exhibit remarkable stability at finite temperatures, making them promising candidates for spintronic applications. Achieving controllable stability and transitions between distinct topological structures is crucial for practical implementations. In this work, we investigate the effect of uniaxial mechanical strain on a magnetic model on the kagome lattice, focusing on skyrmion stability and emergent topological phases. To this end, we consider a Heisenberg model that includes exchange interactions and both in-plane and out-of-plane Dzyaloshinskii-Moriya interactions. Using a combination of Spin-Lattice Dynamics and Monte Carlo simulations, we explore uniaxial strain variations in the range of $-10\%$ to $10\%$, showing important effects on the phase diagram. For compressive strain, we find that the density of skyrmions in the skyrmion gas (SkG) phase can be tuned and that the stability of this phase extends to higher temperatures. Tensile strain, in contrast, reduces the number of skyrmions and promotes transitions to other magnetic states. Within this regime, strain levels of about ($\sim4-6\%$) lead to a change in topological charge, turning skyrmions ($Q=-1$) into antiskyrmions ($Q=+1$). We also examine how strain affects other phases commonly appearing in skyrmion-hosting systems, such as the helical and fully polarized states, showing that mechanical deformation alters their stability and characteristic properties. Finally, we compare these results with the strain response of a more conventional skyrmion model, in order to clarify the role of the different interactions involved. Our results identify strain as an experimentally accessible route for engineering topological spin textures.