Current-driven dynamics and ratchet effect of skyrmion bubbles in a ferrimagnetic insulator

Abstract

Magnetic skyrmions are compact chiral spin textures that exhibit a rich variety of topological phenomena and hold potential for developing high-density memory devices and novel computing schemes driven by spin currents. Here, we demonstrate room temperature interfacial stabilization and current-driven control of skyrmion bubbles in the ferrimagnetic insulator Tm3Fe5O12 (TmIG) coupled to Pt. We track the current-induced motion of individual skyrmion bubbles. The ferrimagnetic order of the crystal together with the interplay of spin-orbit torques and pinning determine the skyrmion dynamics in TmIG and result in a strong skyrmion Hall effect characterized by a negative deflection angle and hopping motion. Further, we show that the velocity and depinning threshold of the skyrmion bubbles can be modified by exchange coupling TmIG to an in-plane magnetized Y3Fe5O12 layer, which distorts the spin texture of the skyrmions and leads to a directional-dependent rectification of their dynamics. This effect, which is equivalent to a magnetic ratchet, is exploited to control the skyrmion flow in a racetrack-like device.

52 pages, 24 figures (manuscript, extended data and supplementary information)

References in corpus (7)

• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Skyrmion Hall Effect Revealed by Direct Time-Resolved X-Ray Microscopy
• The nature of domain walls in ultrathin ferromagnets revealed by scanning nanomagnetometry
• Topological Hall effect at above room temperature in heterostructures composed of a magnetic insulator and a heavy metal
• Magnetic properties and domain structure of ultrathin yttrium iron garnet/Pt bilayers
• Identifying the origin of the non-monotonic thickness dependence of spin-orbit torques and interfacial Dzyaloshinskii-Moriya interaction in a ferrimagnetic insulator heterostructure
• Asymmetric velocity and tilt angle of domain walls induced by spin-orbit torques

Cited by in corpus (5)

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• Terahertz spin ratchet effect in magnetic metamaterials
• Leveraging symmetry for an accurate spin-orbit torques characterization in ferrimagnetic insulators
• A Platform for Addressing Individual Magnetite Islands Grown Epitaxially on Ru(0001) and Manipulating Their Magnetic Domains