Interplay between size and stability of magnetic skyrmions
https://doi.org/10.17586/2220-8054-2018-9-3-356-363
Abstract
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.
Supporting agencies: The authors would like to thank H. J´onsson and V.M. Uzdin for helpful discussions and useful comments. This work is supported by the Russian Science Foundation (Grant No. 17-72-10195).
About the Authors
A. S. Varentsova
TMO University
Russian Federation
Russian Federation
197101 St. Petersburg
M. N. Potkina
St. Petersburg State University; Science Institute, University of Iceland
Russian Federation
Russian Federation
198504 St. Petersburg
107 Reykjav´ık, Iceland
S. von Malottki
Institute of Theoretical Physics and Astrophysics, University of Kiel
Germany
Germany
24098 Kiel
S. Heinze
Institute of Theoretical Physics and Astrophysics, University of Kiel
Germany
Germany
24098 Kiel
P. F. Bessarab
TMO University
Russian Federation
Russian Federation
197101 St. Petersburg
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Review
For citations:
Varentsova A.S., Potkina M.N., Malottki S., Heinze S., Bessarab P.F. Interplay between size and stability of magnetic skyrmions. Nanosystems: Physics, Chemistry, Mathematics. 2018;9(3):356-363. https://doi.org/10.17586/2220-8054-2018-9-3-356-363
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