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arXiv · 1906.11535

Structure of Superconducting Ca-intercalated Bilayer Graphene/SiC studied using Total-Reflection High-Energy Positron Diffraction

Y. Endo·Y. Fukaya·I. Mochizuki·A. Takayama·T. Hyodo·S. Hasegawa
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Abstract

We have investigated the atomic structure of superconducting Ca-intercalated bilayer graphene on a SiC(0001) substrate using total-reflection high-energy positron diffraction. By comparing the experimental rocking-curves with ones calculated for various structural models using a full-dynamical theory, we have found that Ca atoms are intercalated in the graphene-buffer interlayer, rather than between the two graphene layers. From transport measurements, the superconducting transition was observed to be at Tc_onset = 4K for this structure. This study is the first to clearly identify the relation between the atomic arrangement and superconductivity in Ca-intercalated bilayer graphene.

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Y. Endo, Y. Fukaya, I. Mochizuki, A. Takayama, T. Hyodo, S. Hasegawa. 2019-06-27. Structure of Superconducting Ca-intercalated Bilayer Graphene/SiC studied using Total-Reflection High-Energy Positron Diffraction. https://doi.org/10.1016/j.carbon.2019.10.070

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