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arXiv · 1702.00624

Edge-of-edge States

Koji Hashimoto·Taro Kimura·Xi Wu
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Abstract

We study an exotic state which is localized only at an intersection of edges of a topological material. This "edge-of-edge" state is shown to exist generically. We construct explicitly generic edge-of-edge states in 5-dimensional Weyl semimetals and their dimensional reductions, such as 4-dimensional topological insulators of class A and 3-dimensional chiral topological insulators of class AIII. The existence of the edge-of-edge state is due to a topological charge of the edge states. The notion of the Berry connection is generalized to include the space of all possible boundary conditions, where Chern-Simons forms are shown to be nontrivial.

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Koji Hashimoto, Taro Kimura, Xi Wu. 2017-02-12. Edge-of-edge States. https://doi.org/10.1103/physrevb.95.165443

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