Strongly enhanced lifetime of higher-order bimerons and antibimerons

Abstract

Magnetic bimerons, similar to skyrmions, are topologically nontrivial spin textures characterized by topological charge $Q$. Most studies so far have focused on low-$Q$ solitons ($|Q|\le 1$), such as skyrmions, bimerons, and vortices. Here, we present the first calculations of the lifetimes of {ring-like} high-$Q$ bimerons and demonstrate that they are fundamentally more stable than high-$Q$ skyrmions over a wide range of temperature. To obtain realistic results, our chosen system is an experimentally feasible van der Waals interface, Fe${}_3$GeTe${}_2$/Cr${}_2$Ge${}_2$Te${}_6$. We show that the lifetimes of high-$Q$ (anti)bimerons can exceed the lifetime of those with $|Q|=1$ by 3 orders of magnitude. Remarkably, this trend remains valid even when extrapolated to room temperature (RT), as the lifetimes are dominated by entropy rather than energy barriers. This contrasts with high-$Q$ skyrmions, whose lifetimes fall with $|Q|$ near RT. We attribute this fundamental difference between skyrmions and bimerons to their distinct magnetic texture symmetries, which lead to different entropy-dominated lifetimes.

8 pages, 4 figures

References in corpus (11)

• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Magnetic Skyrmion Bundles and Their Current-Driven Dynamics
• Skyrmion Qubits: A New Class of Quantum Logic Elements Based on Nanoscale Magnetization
• Laser-induced topological spin switching in a 2D van der Waals magnet
• Strain-Driven Zero-Field Near-10 nm Skyrmions in Two-Dimensional van der Waals Heterostructures
• Turning chiral skyrmion inside out
• Stability and dynamics of in-plane skyrmions in collinear ferromagnets
• On the scaling behaviour of cross-tie domain wall structures in patterned NiFe elements
• Prediction of stable nanoscale skyrmions in monolayer Fe${}_5$GeTe${}_2$
• Proposal for all-electrical skyrmion detection in van der Waals tunnel junctions
• Topological invariants of vortices, merons, skyrmions, and their combinations in continuous and discrete systems