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arXiv · 2209.02019

Topological edge states in dipolar zig-zag stripes

Paula Mellado
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Abstract

We study the magnon spectrum of stacked zig-zag chains of point magnetic dipoles with an easy axis. The anisotropy due to the dipolar interactions and the two-point basis of the zig-zag chain unit cell combine to give rise to topologically non-trivial magnon bands in 2D zig-zag lattices. Adjusting the distance between the two sublattice sites in the unit cell causes a band touching, which triggers the exchange of the Chern numbers of volume bands switching the sign of the thermal conductivity and the sense of motion of edges modes in zig-zag stripes. We show that these topological features survive when the range of the dipolar interactions is truncated up to the second nearest neighbors.

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Paula Mellado. 2022-09-05. Topological edge states in dipolar zig-zag stripes. https://doi.org/10.1088/2515-7639%2Fac8315

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