najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2025-16-3-317-324najo-320Research ArticleNANOSYSTEMS: PHYSICS, CHEMISTRY, MATHEMATICSНАНОСИСТЕМЫ: ФИЗИКА, ХИМИЯ, МАТЕМАТИКАOptimality of linear vacancy defect for skyrmion nucleationОптимальность линейного вакансионного дефекта для нуклеации скирмионовhttps://orcid.org/0000-0002-1380-2454ПоткинаМ. Н.PotkinaM. N.

Maria N. Potkina – Infochemistry Scientific Center

197101 St. Petersburg

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

Igor S. Lobanov – Faculty of Physics

197101 St. Petersburg

lobanov.igor@gmail.comITMO UniversityRussian Federation202529062025163317324Copyright © 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/320

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.

Магнитные скирмионы открывают перспективу создания сверхплотных и энергоэффективных устройств памяти, однако их эффективная запись остается сложной задачей. Используя атомистическое спиновое моделирование и расчёты путей с минимальным перепадом энергии в пленке PdFe/Ir(111), мы показали, что нанесение линейных цепочек из четырёх атомных вакансий почти вдвое снижает барьер нуклеации скирмиона — до 44,7 мэВ при 3,75 Тл — по сравнению с 85 мэВ в образце без примесей. Линейные дефекты являются наилучшим решением за счёт того, что они исключают области с высокой энергией в ядре во время создания скирмиона, при этом минимально нарушая его  внешнее окружение с плотностью отрицательной энергии при депиннинге. Этот эффект, обусловленный геометрией, основан только на общих профилях плотности энергии, что делает его широко применимым ко всем материалам, способным поддерживать скирмионы.

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