Dynamic Origin of Azimuthal Modes Splitting in Vortex-State Magnetic Dots
Dynamic Origin of Azimuthal Modes Splitting in Vortex-State Magnetic Dots
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DOI：
10.1103/physrevlett.101.247203
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发表时间：
2008-12-12
影响因子：
8.6
通讯作者：
Kim, Sang-Koog
中科院分区：
文献类型：
--
作者：
Guslienko, Konstantin Y.;Slavin, Andrei N.;Kim, Sang-Koog
提出了一种自旋波理论，解释了涡旋基态磁点方位对称的动态自旋激励的频裂现象。结果表明，这种分裂是一个点的三种自旋波模式的偶极杂交的结果，其方位角指数为m=1：涡旋面内部分的两个高频方位角偶极模式，其指数为m=+/- 1，以及描述涡旋核心的平动运动的低频（Goldstone-like）回旋模式，其指数为m=+1。解析计算的分频幅度与点厚度与其半径之比成正比，在定量上与时间分辨克尔实验的结果一致。
A spin-wave theory explaining experimentally observed frequency splitting of dynamical spin excitations with azimuthal symmetry of a magnetic dot in a vortex ground state is developed. It is shown that this splitting is a result of the dipolar hybridization of three spin-wave modes of a dot having azimuthal indices m=1: two high-frequency azimuthal dipolar modes of the in-plane part of the vortex with indices m=+/- 1 and a low-frequency (Goldstone-like) gyrotropic mode, describing translational motion of the vortex core and having index m=+1. The analytically calculated magnitude of the frequency splitting is proportional to the ratio of the dot thickness to its radius and quantitatively agrees with the results of time-resolved Kerr experiments.