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arXiv · 1601.07440

Unified theory of PT and CP invariant topological metals and nodal superconductors

Y. X. Zhao·Andreas P. Schnyder·Z. D. Wang
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Abstract

As PT and CP symmetries are fundamental in physics, we establish a unified topological theory of PT and CP invariant metals and nodal superconductors, based on the mathematically rigorous $KO$ theory. Representative models are constructed for all nontrivial topological cases in dimensions $d=1,2$, and $3$, with their exotic physical meanings being elucidated in detail. Intriguingly, it is found that the topological charges of Fermi surfaces in the bulk determine an exotic direction-dependent distribution of topological subgap modes on the boundaries. Furthermore, by constructing an exact bulk-boundary correspondence, we show that the topological Fermi points of the PT and CP invariant classes can appear as gapless modes on the boundary of topological insulators with a certain type of anisotropic crystalline symmetry.

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Y. X. Zhao, Andreas P. Schnyder, Z. D. Wang. 2016-04-07. Unified theory of PT and CP invariant topological metals and nodal superconductors. https://doi.org/10.1103/physrevlett.116.156402

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