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arXiv · 1905.10465

First-principles study of metal-graphene edge contact for ballistic Josephson junction

Yeonghun Lee·Jeongwoon Hwang·Fan Zhang·Kyeongjae Cho
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Abstract

Edge-contacted superconductor-graphene-superconductor Josephson junction have been utilized to realize topological superconductivity, which have shown superconducting signatures in the quantum Hall regime. We perform the first-principles calculations to interpret electronic couplings at the superconductor-graphene edge contacts by investigating various aspects in hybridization of molybdenum d orbitals and graphene $\pi$ orbitals. We also reveal that interfacial oxygen defects play an important role in determining the doping type of graphene near the interface.

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Yeonghun Lee, Jeongwoon Hwang, Fan Zhang, Kyeongjae Cho. 2019-05-24. First-principles study of metal-graphene edge contact for ballistic Josephson junction. https://doi.org/10.1103/physrevmaterials.3.064801

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