najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2024-15-2-192-200najo-62Research ArticlePHYSICSФИЗИКАNucleation of magnetic skyrmions at a notchНуклеация магнитных скирмионов на вырезеhttps://orcid.org/0000-0002-1380-2454ПоткинаМ. Н.PotkinaM. N.

Maria N. Potkina.

197101 St. Petersburg

potkina.maria@yandex.ruhttps://orcid.org/0000-0001-8789-3267ЛобановИ. С.LobanovI. S.

Igor S. Lobanov.

197101 St. Petersburg

lobanov.igor@gmail.comInfochemistry Scientific Center, ITMO UniversityRussian FederationFaculty of Physics, ITMO UniversityRussian Federation202431052025152192200Copyright © Potkina M.N., Lobanov I.S., 20252025Поткина М.Н., Лобанов И.С.Potkina M.N., Lobanov I.S.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/62

Magnetic skyrmions are considered promising candidates for coding bits of information in racetrack memory devices. Information recording in such devices is assumed to occur by creating skyrmions. This work is devoted to finding solutions to make this process as energy-efficient as possible. One of the factors influencing the creation of skyrmions is the geometry of the track on which recording takes place. We study the influence of the shape and size of track boundary notches on the energy barriers of skyrmion nucleation. We show that skyrmions generation is facilitated by the presence of irregularities at the track boundary and the best solution is a deep narrow notch. On the other hand the skyrmion nucleation rate is smaller for smooth boundaries and skyrmions generation can be suppressed by their interaction with the track boundary, if notch size is smaller than the skyrmion radius. These results can be used in development of future memory devices based on skyrmions.

Магнитные скирмионы считаются перспективными кандидатами для кодирования битов информации в устройствах беговой магнитной памяти. Запись информации в таких устройствах происходит путем создания скирмионов. Данная работа посвящена поиску подходов, позволяющих сделать этот процесс максимально энергоэффективным. Одним из факторов, влияющих на создание скирмионов, является геометрия трека, на котором происходит запись. Мы изучили влияние формы и размера вырезов на границах треков на энергетические барьеры зарождения скирмионов. Показано, что наличие неровностей на границе трека способствует генерации скирмионов и лучшим решением является глубокий узкий вырез. С другой стороны, скорость зарождения скирмионов меньше для гладких границ, и генерация скирмионов может быть подавлена их взаимодействием с границей трека, если размер выреза меньше радиуса скирмиона. Эти результаты могут быть использованы при разработке будущих устройств памяти на основе скирмионов.

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The authors declare that there are no conflicts of interest present.