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arXiv · 1911.12523

Weyl superconductor phases in a Weyl-semimetal/superconductor multilayer

Ryota Nakai·Kentaro Nomura
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Abstract

Topologically nontrivial superconducting phases have been engineered in topological materials by the proximity effect in contact with conventional superconductors. In this paper, by using the method of the Kronig-Penney model, we study the superconducting proximity effect in the bulk electronic states of Weyl semimetals by considering a multilayer structure consisting of Weyl-semimetal and superconductor layers. Due to the proximity effect, two Weyl nodes are decoupled into four nodes of Majorana fermions resulting in Weyl-superconductor phases or three-dimensional extension of topological-superconductor phases. We find that mismatch of the Fermi velocity and potential barriers at the interface gap out Majorana nodes, thus turn Weyl-superconductor phases with four Majorana nodes into Weyl-superconductor phases with half of Majorana nodes and topological-superconductor phases with odd integer Chern numbers.

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Ryota Nakai, Kentaro Nomura. 2020-03-13. Weyl superconductor phases in a Weyl-semimetal/superconductor multilayer. https://doi.org/10.1103/physrevb.101.094510

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