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arXiv · 2008.12590

Square-root topological semimetals

Tomonari Mizoguchi·Tsuneya Yoshida·Yasuhiro Hatsugai
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Abstract

We propose topological semimetals generated by the square-root operation for tight-binding models in two and three dimensions, which we call square-root topological semimetals. The square-root topological semimetals host topological band touching at finite energies, whose topological protection is inherited from the squared Hamiltonian. Such a topological character is also reflected in emergence of boundary modes with finite energies. Specifically, focusing on topological properties of squared Hamiltonian in class AIII, we reveal that a decorated honeycomb (decorated diamond) model hosts finite-energy Dirac cones (nodal lines). We also propose a realization of a square-root topological semimetal in a spring-mass model, where robustness of finite-energy Dirac points against the change of tension is elucidated.

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Tomonari Mizoguchi, Tsuneya Yoshida, Yasuhiro Hatsugai. 2021-02-03. Square-root topological semimetals. https://doi.org/10.1103/physrevb.103.045136

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