Creating and\nDeleting a Single Dipolar Skyrmion by\nSurface Spin Twists

We report deterministic operations on single dipolar\nskyrmions\nconfined in nanostructured cuboids by using in-plane currents. We\nachieve highly reversible writing and deleting of skyrmions in a simple\ncuboid without any artificial defects or pinning sites. The current-induced\ncreation of skyrmions is well-understood through the spin-transfer\ntorque acting on surface spin twists of the spontaneous 3D ferromagnetic\nstate, caused by the magnetic dipole–dipole interaction of\nthe uniaxial Fe<sub>3</sub>Sn<sub>2</sub> magnet with a low-quality\nfactor. Current-induced deletions of skyrmions result from the combined\neffects of magnetic hysteresis and Joule thermal heating. Our results\nare replicated consistently through 3D micromagnetic simulations.\nOur approach offers a viable method for achieving reliable single-bit\noperations in skyrmionic devices for applications such as random-access\nmemories.