Indications of superconductivities in blend of variant apatite and covellite

Hongyang Wang; Yijing Zhao; Hao Wu; Ling Wang; Zhixing Wu; Zhihui Geng; Jiewen Xiao; Weiwei Xue; Shufeng Ye; Ning Chen; Xianfeng Qiao; Yao Yao

arXiv · 2406.17525

Indications of superconductivities in blend of variant apatite and covellite

Hongyang Wang·Yijing Zhao·Hao Wu·Ling Wang·Zhixing Wu·Zhihui Geng·Jiewen Xiao·Weiwei Xue·Shufeng Ye·Ning Chen·Xianfeng Qiao·Yao Yao

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Abstract

Through heavily doping sulfur into an apatite framework, we synthesize a new blend mainly comprising variant apatite and covellite (copper sulfide). Magnetic measurement exhibits that significant diamagnetism appears at around 260 K and drops dramatically below 30 K implying coexistence of two superconducting phases. The upper critical magnetic field is larger than 1000 Oe at 250 K. Electric measurement manifests that the current-voltage curves deviate from the normal linear lineshape suggesting the presence of zero-resistance effect, and the critical current is around 50 $\mu$A at 140 K. These exotic magnetic and electric features strongly indicate these two components, variant apatite and covellite, individually trigger two superconducting phases at near-room and low temperatures.

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Hongyang Wang, Yijing Zhao, Hao Wu, Ling Wang, Zhixing Wu, Zhihui Geng, Jiewen Xiao, Weiwei Xue, Shufeng Ye, Ning Chen, Xianfeng Qiao, Yao Yao. 2024-06-25. Indications of superconductivities in blend of variant apatite and covellite. https://arxiv.org/abs/2406.17525

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