2014/11/11 by Jan Müller, Achim Rosch · 1 citation
Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #Classical mechanics #Condensed matter physics #Current (fluid) #Magnet #Magnetic field #Magnetic properties of thin films #Motion (physics) #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #RADIUS #Skyrmion #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.91.054410
published as Phys. Rev. B 91, 054410 (2015) · 11 pages
arxiv created 2014/11/11 · openalex publication_date 2015/02/17 · arxiv updated 2015/03/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Magnetic whirls in chiral magnets, so-called skyrmions, can be manipulated by ultrasmall current densities. Here we study both analytically and numerically the interactions of a single skyrmion in two dimensions with a small hole in the magnetic layer. Results from micromagnetic simulations are in good agreement with effective equations of motion obtained from a generalization of the Thiele approach. Skyrmion-defect interactions are described by an effective potential with both repulsive and attractive components. For small current densities a previously pinned skyrmion stays pinned whereas an unpinned skyrmion moves around the impurities and never gets captured. For higher current densities, jc1<j<jc2, however, single holes are able to capture moving skyrmions. The maximal cross section is proportional to the skyrmion radius and to √\ensuremathα, where \ensuremathα is the Gilbert damping. For j>jc2 all skyrmions are depinned. Small changes of the magnetic field strongly change the pinning properties; one can even reach a regime without pinning, jc2=0. We also show that a small density of holes can effectively accelerate the motion of the skyrmion and introduce a Hall effect for the skyrmion.