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arXiv · 1304.6477

Specular Andreev Reflection in Inversion-symmetric Weyl-semimetals

Wei Chen·Liang Jiang·R. Shen·L. Sheng·B. G. Wang·D. Y. Xing
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Abstract

The electron-hole conversion at the normal-metal superconductor interface in inversion-symmetric Weyl semimetals is investigated with an effective two-band model. We find that the specular Andreev reflection of Weyl fermions has two unusual features. The Andreev conductance for s-wave BCS pairing states is anisotropic, depending on the angle between the line connecting a pair of Weyl points and the normal of the junction, due to opposite chirality carried by the paired electrons. For the Fulde-Ferrell-Larkin-Ovchinnikov pairing states, the Andreev reflection spectrum is isotropic and is independent of the finite momentum of the Cooper pairs.

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Wei Chen, Liang Jiang, R. Shen, L. Sheng, B. G. Wang, D. Y. Xing. 2013-07-23. Specular Andreev Reflection in Inversion-symmetric Weyl-semimetals. https://doi.org/10.1209/0295-5075%2F103%2F27006

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