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arXiv · 1805.02598

Higher-order bulk-boundary correspondence for topological crystalline phases

Luka Trifunovic·Piet W. Brouwer
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Abstract

We study the bulk-boundary correspondence for topological crystalline phases, where the crystalline symmetry is an order-two (anti)symmetry, unitary or antiunitary. We obtain a formulation of the bulk-boundary correspondence in terms of a subgroup sequence of the bulk classifying groups, which uniquely determines the topological classification of the boundary states. This formulation naturally includes higher-order topological phases as well as topologically nontrivial bulk systems without topologically protected boundary states. The complete bulk and boundary classification of higher-order topological phases with an additional order-two symmetry or antisymmetry is contained in this work.

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Luka Trifunovic, Piet W. Brouwer. 2018-05-07. Higher-order bulk-boundary correspondence for topological crystalline phases. https://doi.org/10.1103/physrevx.9.011012

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