Optimality of linear vacancy defect for skyrmion nucleation
https://doi.org/10.17586/2220-8054-2025-16-3-317-324
Abstract
Magnetic skyrmions offer a pathway to ultra-dense, low-power memory, but writing them efficiently remains a challenge. Using atomistic spin simulations and minimum energy path calculations in a PdFe/Ir(111) film, we show that deliberately placing linear chains of four atomic vacancies cuts the skyrmion nucleation barrier nearly in half-down to 44.7 meV at 3.75 T-compared to 85 meV in a pristine track. Linear defects excel because they remove high-energy core regions during skyrmion creation while minimally disturbing its outer negative energy halo during depinning. This geometry-driven effect relies only on generic energy density profiles, making it broadly applicable to all skyrmion-hosting materials.
Supporting agencies: The study was supported by the Russian Science Foundation grant No. 24-72-00089, https://rscf.ru/en/project/24-72-00089/.
About the Authors
M. N. Potkina
ITMO University
Russian Federation
Russian Federation
Maria N. Potkina – Infochemistry Scientific Center
197101 St. Petersburg
I. S. Lobanov
ITMO University
Russian Federation
Russian Federation
Igor S. Lobanov – Faculty of Physics
197101 St. Petersburg
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For citations:
Potkina M.N., Lobanov I.S. Optimality of linear vacancy defect for skyrmion nucleation. Nanosystems: Physics, Chemistry, Mathematics. 2025;16(3):317-324. https://doi.org/10.17586/2220-8054-2025-16-3-317-324
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