Models of the energy landscape for an element of shakti spin ice
https://doi.org/10.17586/2220-8054-2018-9-6-711-715
Abstract
Micromagnetic calculations are compared with faster model calculations of interacting nanoscopic magnetic islands representing an element of a shakti spin ice lattice. Several pathways for transitions between equivalent ground states are studied. The model calculations describe the interaction between the islands either with the point dipole approximation, or with a dumbbell approximation where the distance between the two poles is optimized to match the micromagnetic results. The closest agreement in the energy of both local minima as well as transition state configurations where one macrospin has rotated by 90◦ is obtained with a dumbbell model where the distance between the poles is ca. 20 % smaller than the island length.
Keywords
Supporting agencies: This work was funded by Icelandic Research Fund (grants no. 152483-051, 185405-051, 163048-053 and 184949-051), University of Iceland Research Fund and Russian Foundation of Basic Research (grant RFBR 18-0200267 A). The calculations were performed on resources provided by the Icelandic High Performance Computing Centre at the University of Iceland.
About the Authors
U. B. Arnalds
Science Institute, University of Iceland
Ireland
Ireland
107 Reykjav´ık
S. Y. Liashko
Science Institute, University of Iceland; ITMO University
Iceland
Iceland
107 Reykjav´ık
49, St. Petersburg, 197101
P. F. Bessarab
Science Institute, University of Iceland; ITMO University
Ireland
Ireland
107 Reykjav´ık
49, St. Petersburg, 197101
V. M. Uzdin
ITMO University; St. Petersburg State University
Russian Federation
Russian Federation
49, St. Petersburg, 197101
St. Petersburg, 198504
H. Jonsson´
Faculty of Physical Sciences, University of Iceland; Dept. of Applied Physics, Aalto University
Ireland
Ireland
107 Reykjav´ık
Espoo, FI-00076, Finland
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Review
For citations:
Arnalds U.B., Liashko S.Y., Bessarab P.F., Uzdin V.M., Jonsson´ H. Models of the energy landscape for an element of shakti spin ice. Nanosystems: Physics, Chemistry, Mathematics. 2018;9(6):711–715. https://doi.org/10.17586/2220-8054-2018-9-6-711-715
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