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arXiv · 1207.5382

Pressure effects on superconducting properties of single-crystalline Co doped NaFeAs

A. F. Wang·Z. J. Xiang·J. J. Ying·Y. J. Yan·P. Cheng·G. J. Ye·X. G. Luo·X. H. Chen
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Abstract

Resistivity and magnetic susceptibility measurements under external pressure were performed on single-crystals NaFe1-xCoxAs (x=0, 0.01, 0.028, 0.075, 0.109). The maximum Tc enhanced by pressure in both underdoped and optimally doped NaFe1-xCoxAs is the same, as high as 31 K. The overdoped sample with x = 0.075 also shows a positive pressure effect on Tc, and an enhancement of Tc by 13 K is achieved under pressure of 2.3 GPa. All the superconducting samples show large positive pressure coefficient on superconductivity, being different from Ba(Fe1-xCox)2As2. However, the superconductivity cannot be induced by pressure in heavily overdoped non-superconducting NaFe0.891Co0.109As. These results provide evidence for that the electronic structure is much different between superconducting and heavily overdoped non-superconducting NaFe1-xCoxAs, being consistent with the observation by angle-resolved photoemission spectroscopy.

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A. F. Wang, Z. J. Xiang, J. J. Ying, Y. J. Yan, P. Cheng, G. J. Ye, X. G. Luo, X. H. Chen. 2012-07-23. Pressure effects on superconducting properties of single-crystalline Co doped NaFeAs. https://doi.org/10.1088/1367-2630/14/11/113043

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