NANOSYSTEMS: PHYSICS, CHEMISTRY, MATHEMATICS, 2018, 9 (3), P. 356–363
Interplay between size and stability of magnetic skyrmions
A. S. Varentsova – ITMO University, 197101 St. Petersburg, Russia; varentsova.a@mail.ru
M. N. Potkina – St. Petersburg State University, 198504 St. Petersburg, Russia; Science Institute, University of Iceland, 107 Reykjavík, Iceland
S. von Malottki – Institute of Theoretical Physics and Astrophysics, University of Kiel, 24098 Kiel, Germany
S. Heinze – Institute of Theoretical Physics and Astrophysics, University of Kiel, 24098 Kiel, Germany
P. F. Bessarab – ITMO University, 197101 St. Petersburg, Russia; bessarab@hi.is
The relationship between the size and stability of isolated skyrmions in a magnetic monolayer is analyzed based on minimum energy path calculations and atomistic spin Hamiltonian. It is demonstrated that the energy barrier protecting the skyrmion from collapse to the ferromagnetic state is not uniquely defined by the skyrmion size, although these two properties as functions of relevant material parameters follow similar trends. Stability of nanoscale skyrmions can be enhanced by a concerted adjustment of material parameters. The proposed parameter transformation conserves the skyrmion size, but does not conserve the skyrmion shape which changes from an arrow-like pattern to a profile that resembles magnetic bubbles. This transformation of the skyrmion shape is accompanied by an increase in the collapse energy barrier and thus enhancement of skyrmion stability.
Keywords: magnetic skyrmion, thermal stability, energy barrier.
PACS 75.70.Ak, 75.70.Kw
DOI 10.17586/2220-8054-2018-9-3-356-363
