najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2018-9-6-711-715najo-720Research ArticlePHYSICSФИЗИКАModels of the energy landscape for an element of shakti spin iceArnaldsU. B.

107 Reykjav´ık

LiashkoS. Y.

107 Reykjav´ık

49, St. Petersburg, 197101

BessarabP. F.

107 Reykjav´ık

49, St. Petersburg, 197101

UzdinV. M.

49, St. Petersburg, 197101

St. Petersburg, 198504

v_uzdin@mail.ruJonsson´H.

107 Reykjav´ık

Espoo, FI-00076, Finland 

Science Institute, University of IcelandIrelandScience Institute, University of Iceland; ITMO UniversityIcelandITMO University; St. Petersburg State UniversityRussian FederationFaculty of Physical Sciences, University of Iceland; Dept. of Applied Physics, Aalto UniversityIreland20181408202596711–715Copyright © Arnalds U.B., Liashko S.Y., Bessarab P.F., Uzdin V.M., Jonsson´ H., 20252025Arnalds U.B., Liashko S.Y., Bessarab P.F., Uzdin V.M., Jonsson´ H.Arnalds U.B., Liashko S.Y., Bessarab P.F., Uzdin V.M., Jonsson´ H.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/720

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.

magnetic islandsactivation energymicromagneticsdipole interactiondumbbellspin iceThis 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.ReferencesWang R.F., Nisoli C., Freitas R.S., Li J., McConville W., Cooley B.J., Lund M.S., Samarth N., Leighton C., Crespi V.H. and Schiffer P. Artificial ‘spin ice’ in a geometrically frustrated lattice of nanoscale ferromagnetic islands. Nature, 2006, 439, P. 303–306.Wang R.F., Nisoli C., Freitas R.S., Li J., McConville W., Cooley B.J., Lund M.S., Samarth N., Leighton C., Crespi V.H. and Schiffer P. Artificial ‘spin ice’ in a geometrically frustrated lattice of nanoscale ferromagnetic islands. 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The authors declare that there are no conflicts of interest present.