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arXiv · 1604.02840

Topological Hopf-Chern Insulators and the Hopf Superconductor

Ricardo Kennedy
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Abstract

We introduce new three-dimensional topological phases of two-band models using the Pontryagin-Thom construction. In symmetry class A these are the infinitely many Hopf-Chern topological insulators, which are hybrids of layered Chern insulators and the Hopf insulator. In symmetry class C, there is a $\mathbb{Z}_2$-classification with the non-trivial topological phase, the Hopf superconductor, being realized by a construction that doubles the usual Hopf insulator in momentum space. For these new topological phases we investigate the energy spectrum in the presence of a boundary and find gapless surface modes, confirming the validity of the bulk-boundary correspondence.

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Ricardo Kennedy. 2016-04-11. Topological Hopf-Chern Insulators and the Hopf Superconductor. https://doi.org/10.1103/physrevb.94.035137

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