Magnetic skyrmion which is a quasi-particle whose spins cover a unit sphere has attracted much attention because of various emergent exotic spin-dependent phenomena due to non-trivial topology in real space . Room-temperature magnetic skyrmion has been demonstrated in heavy metal/ ferromagnet systems due to an interfacial Dzyaloshinskii-Moriya interaction (DMI) induced by strong spin-orbit coupling . The spin-orbit coupling also gives rise to spin-orbit torques (SOTs) under in-plane current, allowing efficient control of the skyrmion . However, there still remain some fundamental issues for applications. For instance, skyrmion Hall effect (SkHE), a diagonal motion of skyrmion with respect to the current direction owing to the Magnus force [4], limits the velocity of skyrmion motion on a track . In addition, large stray-field in ferromagnetic multilayer system imposes a limit on scaling of skyrmion-based device concepts . Theoretical studies predicted that antiferromagnetic skyrmions are free from these limitations . Experimentally, skyrmion Hall effect-free motion has been achieved in ferrimagnetic alloy, although the emergence of favorable features is limited at an angular-momentum compensation temperature.
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