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arXiv · 0912.2025

Superconductivity at 31 K in 111 type iron arsenide superconductor NaxFeAs induced by pressure

S. J. Zhang·X. C. Wang·Q. Q. Liu·Y. X. Lv·X. H. Yu·Z. J. Lin.·Y. S. Zhao·L. Wang·Y. Ding·H. K. Mao·C. Q. Jin
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Abstract

The effect of pressure on superconductivity of 111 type NaxFeAs is investigated through temperature dependent electrical resistance measurement in a diamond anvil cell. The superconducting transition temperature (Tc) increases from 26 K to a maximum 31 K as the pressure increases from ambient to 3 GPa. Further increasing pressure suppresses Tc drastically. The behavior of pressure tuned Tc in NaxFeAs is much different from that in LixFeAs, although they have the same Cu2Sb type structure

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S. J. Zhang, X. C. Wang, Q. Q. Liu, Y. X. Lv, X. H. Yu, Z. J. Lin., Y. S. Zhao, L. Wang, Y. Ding, H. K. Mao, C. Q. Jin. 2009-12-10. Superconductivity at 31 K in 111 type iron arsenide superconductor NaxFeAs induced by pressure. https://doi.org/10.1209/0295-5075%2F88%2F47008

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