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arXiv · 2003.01144

Higher-order topological band structures

Luka Trifunovic·Piet W. Brouwer
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Abstract

The interplay of topology and symmetry in a material's band structure may result in various patterns of topological states of different dimensionality on the boundary of a crystal. The protection of these "higher-order" boundary states comes from topology, with constraints imposed by symmetry. We review the bulk-boundary correspondence of topological crystalline band structures, which relates the topology of the bulk band structure to the pattern of the boundary states. Furthermore, recent advances in the K-theoretic classification of topological crystalline band structures are discussed.

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Luka Trifunovic, Piet W. Brouwer. 2020-03-02. Higher-order topological band structures. https://doi.org/10.1002/pssb.202000090

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