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arXiv · 1709.01561

Weyl nodal surfaces

Oğuz Türker·Sergej Moroz
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Abstract

We consider three-dimensional fermionic band theories that exhibit Weyl nodal surfaces defined as two-band degeneracies that form closed surfaces in the Brillouin zone. We demonstrate that topology ensures robustness of these objects under small perturbations of a Hamiltonian. This topological robustness is illustrated in several four-band models that exhibit nodal surfaces protected by unitary or anti-unitary symmetries. Surface states and Nielsen-Ninomiya doubling of nodal surfaces are also investigated.

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Oğuz Türker, Sergej Moroz. 2018-02-28. Weyl nodal surfaces. https://doi.org/10.1103/physrevb.97.075120

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