Superconducting Klein and anti-Klein tunneling in Weyl junctions

Jiajia Huang; Luyang Wang; Dao-Xin Yao

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arXiv · 2404.16738

Superconducting Klein and anti-Klein tunneling in Weyl junctions

Jiajia Huang·Luyang Wang·Dao-Xin Yao

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Abstract

Klein tunneling is an old topic in relativistic quantum physics, and has been observed recently in graphene where massless particles reside. Here, we propose a new heterostructure platform for Klein tunneling to occur, which consists of a Weyl-semimetal-based normal state/superconductor (NS) junction. By developing a Blonder-Tinkham-Klapwijk-like theory, we find that Klein tunneling occurs at normal incidence, which can lead to differential conductance doubling. If the (single) Weyl semimeltals are replaced by double Weyl semimetals, anti-Klein tunneling will take place of Klein tunneling. Our work provides a theoretical guide for the detection of (anti-)Klein tunneling in three-dimensional chiral NS junctions.

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Jiajia Huang, Luyang Wang, Dao-Xin Yao. 2024-04-25. Superconducting Klein and anti-Klein tunneling in Weyl junctions. https://arxiv.org/abs/2404.16738

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