Удивительная история длиннопериодических спиновых осцилляций в синтетических антиферромагнетиках: некоторые точные решения
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Аннотация
Данная работа посвящена построению математической теории, корректно объясняющей экспериментально наблюдаемые периодические осцилляции намагниченности в синтетическом антиферромагнетике Pt/Co/Ir/Co/Pt при изменении направления внешнего магнитного поля. Показано, что существенную роль в модели играют столкновения друг с другом магнитных доменов различной спиновой ориентированности
Abstract
This article is devoted to construction of a mathematical theory capable of explaining those experimentally observable periodic magnetic oscillations in the synthetic antiferromagnet Pt/Co/Ir/Co/Pt that take place after a switch in the direction of an external magnetic field. In particular, we demonstrate that in order to understand the aforementioned phenomenon it is essential to first properly model the collisions between the magnetic domains of different spin orientations ( and ). The resulting model comprised of a system of nonlinear differential equations is closely examined, after which we propose a simple analytical method of construction of its exact solutions. This method is shown to generate an infinite family of solutions associated with the degenerate hypergeometric functions, parameterized by a natural number N. One of those solutions with N = 2 produces the magnetization function which perfectly fits the experimental data.
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