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Particle‐like magnetic textures with nanometric sizes, such as skyrmions, are potentially suitable for designing high‐efficiency information bits in future spintronics devices. In general, the Dzyaloshinskii–Moriya interactions and dipolar interactions are the dominant factors for generating nonlinear spin configurations. However, to stabilize the topological skyrmions, an external magnetic field is usually required. In this study, the spontaneous emergence of skyrmions is directly observed, together with the unique successive topological domain evolution during the spin reorientation transition in a neodymium–cobalt (NdCo5) rare‐earth magnet. On decreasing the temperature, nanometric skyrmion lattices evolve into enclosed in‐plane domains (EIPDs) similar to mini bar‐magnets with size below 120 nm. The internal magnetization rotates with magnetic anisotropy, demonstrating the ability to manipulate the mini bar‐magnets. The nanoscale EIPD lattices remain robust over the wide temperature range of 241–167 K, indicating the possibility of high‐density in‐plane magnetic information storage. The generation of spontaneous magnetic skyrmions and the successive domain transformation in the traditional NdCo5 rare‐earth magnet may prompt application exploration for topological magnetic spin textures with novel physical mechanisms in versatile magnets.

L10-FePt nanoparticles dispersed by stirring, ultrasonication and the addition of a surfactant perform better than the aggregated nanoparticles, when aligning.

The magnetic transition, transport properties, and magnetic domain structures of the polycrystalline Mn1.9Fe1.1Sn compound with a hexagonal structure have been investigated. The result shows that ferromagnetic and antiferromagnetic phases coexist in this compound. A large topological Hall effect up to 3.5 μΩ·cm at 50 K has been found due to the formation of noncoplanar spin structures when the competition occurs among magnetocrystalline anisotropy, antiferromagnetic coupling, and ferromagnetic interaction at low temperature. The result of in situ Lorentz transmission electron microscopy cooling experiment at zero field indicates two shapes of domain walls containing vortexes coexisting simultaneously in the compound.

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