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arXiv · 1710.09998

Bulk and edge spin transport in topological magnon insulators

Andreas Rückriegel·Arne Brataas·Rembert A. Duine
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Abstract

We investigate the spin transport properties of a topological magnon insulator, a magnetic insulator characterized by topologically nontrivial bulk magnon bands and protected magnon edge modes located in the bulk band gaps. Employing the Landau-Lifshitz-Gilbert phenomenology, we calculate the spin current driven through a normal metal$|$topological magnon insulator$|$normal metal heterostructure by a spin accumulation imbalance between the metals, with and without random lattice defects. We show that bulk and edge transport are characterized by different length scales. This results in a characteristic system size where the magnon transport crosses over from being bulk-dominated for small systems to edge-dominated for larger systems. These findings are generic and relevant for topological transport in systems of nonconserved bosons.

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Andreas Rückriegel, Arne Brataas, Rembert A. Duine. 2018-02-15. Bulk and edge spin transport in topological magnon insulators. https://doi.org/10.1103/physrevb.97.081106

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