Two-dimensional topological solitons: Canonical Hamilton dynamics and semiclassical description
DOI (Low Temperature Physics):
https://doi.org/10.1063/10.0044127Ключові слова:
topological magnetic soliton, guiding-center coordinates, soliton effective mass, Hofstadter butterflyАнотація
Обговорено динаміку двовимірних топологічних магнітних солітонів. Проведено порівняння з динамікою інших топологічних солітонів, відомих для двовимірних джозефсонівських переходів. Розглядаються джерела ефективної маси солітона для різних моделей магнетиків. Для загальних рівнянь координат цих магнітних солітонів, з додаванням інерційного члена до стандартного суто гіроскопічного рівняння Тіле, будуються пари канонічних гамільтонових змінних, що відкриває прямий шлях до квазікласичного квантування цієї динаміки. Одна пара цих змінних відповідає координатам провідного центру солітона; очікується, що цей рух буде повільним. Для вільного руху солітона динаміка другої пари нагадує стандартну ларморову прецесію зарядженої частинки. Оцінено ефекти взаємного впливу цих двох ступенів вільності для загального вигляду потенціальних сил, що діють на солітон. У рамках простого наближення, що ґрунтується на рівнянні Тіле, виявлено інерційні ефекти для руху солітона в довгих магнітних смугах та появу фрактального солітонного спектра типу метелика Гофштадтера для систем із реальними спіновими ґратками.
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