Manipulation of magnetic spin textures at room temperature in a van der Waals ferromagnet

Topologically protected spin textures, such as skyrmions and antiskyrmions, have garnered considerable attention in the past decade. Although theoretical models have proposed various mechanisms for stabilizing antiskyrmions, their experimental realization has predominantly been limited to systems exhibiting anisotropic Dzyaloshinskii-Moriya interactions and specific symmetry classes, such as D2d or S4. Alternatively, the stabilization of antiskyrmions can be achieved through the manipulation of the interplay between long-range dipolar interactions and exchange interactions. In this paper, we report the observation of dipolar-stabilized skyrmions and antiskyrmions in the van der Waals magnet Fe3GaTe2 (FGT) across a broad temperature range (100-370 K) without the need of an external magnetic field. By manipulating thermal agitation to modulate the strength of perpendicular magnetic anisotropy, we were able to precisely control the formation of skyrmions and antiskyrmions, as observed using Lorentz transmission electron microscopy. We further demonstrate the presence of multitopological spin textures in FGT and their reversible transformations, which were controlled through a history-dependent magnetic field sweep process. These phenomena were characterized using magnetic force microscopy. In this paper, we provide experimental evidence for the existence of topological quasiparticles in two-dimensional systems.