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arXiv · 1303.1630

Chiral spin-wave edge modes in dipolar magnetic thin films

Ryuichi Shindou·Jun-ichiro Ohe·Ryo Matsumoto·Shuichi Murakami·Eiji Saitoh
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Abstract

Based on a linearized Landau-Lifshitz equation, we show that two-dimensional periodic allay of ferromagnetic particles coupled with magnetic dipole-dipole interactions supports chiral spin-wave edge modes, when subjected under the magnetic field applied perpendicular to the plane. The mode propagates along a one-dimensional boundary of the system in a unidirectional way and it always has a chiral dispersion within a band gap for spin-wave volume modes. Contrary to the well-known Damon-Eshbach surface mode, the sense of the rotation depends not only on the direction of the field but also on the strength of the field; its chiral direction is generally determined by the sum of the so-called Chern integers defined for spin-wave volume modes below the band gap. Using simple tight-binding descriptions, we explain how the magnetic dipolar interaction endows spin-wave volume modes with non-zero Chern integers and how their values will be changed by the field.

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Ryuichi Shindou, Jun-ichiro Ohe, Ryo Matsumoto, Shuichi Murakami, Eiji Saitoh. 2013-03-07. Chiral spin-wave edge modes in dipolar magnetic thin films. https://doi.org/10.1103/physrevb.87.174402

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