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arXiv · 1709.01026

Antichiral edge states in a modified Haldane nanoribbon

E. Colomés·M. Franz
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Abstract

Topological phases of fermions in two-dimensions are often characterized by chiral edge states. By definition these propagate in the opposite directions at the two parallel edges when the sample geometry is that of a rectangular strip. We introduce here a model which exhibits what we call "antichiral" edge modes. These propagate in the same direction at both parallel edges of the strip and are compensated by counter-propagating modes that reside in the bulk. General arguments and numerical simulations show that backscattering is suppressed even when strong disorder is present in the system. We propose a feasible experimental realization of a system showing such antichiral edge modes in transition metal dichalcogenide monolayers.

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E. Colomés, M. Franz. 2017-09-04. Antichiral edge states in a modified Haldane nanoribbon. https://doi.org/10.1103/physrevlett.120.086603

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