Superconducting proximity effect and Majorana flat bands in the surface of a Weyl semimetal

Anffany Chen; M. Franz

doi:10.1103/physrevb.93.201105

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arXiv · 1601.01727

Superconducting proximity effect and Majorana flat bands in the surface of a Weyl semimetal

Anffany Chen·M. Franz

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Abstract

We study the proximity effect between an s-wave superconductor (SC) and the surface states of a Weyl semimetal. An interesting two-dimensional SC forms in such an interface with properties resembling in certain aspects the Fu-Kane superconductor with some notable differences. In a Weyl semimetal with unbroken time reversal symmetry the interface SC supports completely flat Majorana bands in a linear Josephson junction with a π phase difference. We discuss stability of these bands against disorder and propose ways in which they can be observed experimentally.

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Anffany Chen, M. Franz. 2016-05-26. Superconducting proximity effect and Majorana flat bands in the surface of a Weyl semimetal. https://doi.org/10.1103/physrevb.93.201105

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