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arXiv · 2305.00444

Superconductivity in graphite intercalation compounds with sodium

Chun-Mei Hao·Xing Li·Artem R. Oganov·Jingyu Hou·Shicong Ding·Yanfeng Ge·Lin Wang·Xiao Dong·Hui-Tian Wang·Guochun Yang·Xiang-Feng Zhou·Yongjun Tian
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Abstract

The discovery of superconductivity in CaC6 with a critical temperature (Tc) of 11.5 K reignites much interest in exploring high-temperature superconductivity in graphite intercalation compounds (GICs). Here we identify a GIC NaC4, discovered by ab initio evolutionary structure search, as a superconductor with a computed Tc of 41.2 K at 5 GPa. This value is eight times higher than that of the synthesized GIC NaC2 and possesses the highest Tc among available GICs. The remarkable superconductivity of GIC NaC4 mainly arises from the coupling of {\pi} electrons in graphene with the low-frequency vibrations involving both Na and C atoms. These findings suggest that Na-GICs may hold great promise as high-Tc superconductors.

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Chun-Mei Hao, Xing Li, Artem R. Oganov, Jingyu Hou, Shicong Ding, Yanfeng Ge, Lin Wang, Xiao Dong, Hui-Tian Wang, Guochun Yang, Xiang-Feng Zhou, Yongjun Tian. 2023-04-30. Superconductivity in graphite intercalation compounds with sodium. https://arxiv.org/abs/2305.00444

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