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arXiv · 0811.3466

Anisotropic, Intermediate Coupling Superconductivity in Cu0.03TaS2

Abstract

The anisotropic superconducting state properties in Cu0.03TaS2 have been investigated by magnetization, magnetoresistance, and specific heat measurements. It clearly shows that Cu0.03TaS2 undergoes a superconducting transition at TC = 4.03 K. The obtained superconducting parameters demonstrate that Cu0.03TaS2 is an anisotropic type-II superconductor. Combining specific heat jump = 1.6(4), gap ratio 2/kBTC = 4.0(9) and the estimated electron-phonon coupling constant ~ 0.68, the superconductivity in Cu0.03TaS2 is explained within the intermediate coupling BCS scenario. First-principles electronic structure calculations suggest that copper intercalation of 2H-TaS2 causes a considerable increase of the Fermi surface volume and the carrier density, which suppresses the CDW fluctuation and favors the raise of TC.

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X. D. Zhu, Y. P. Sun, S. H. Zhang, J. L. Wang, L. J. Zou, L. E. Delong, G. Cao, X. B. Zhu, X. Luo, B. S. Wang, G. Li, Z. R. Yang, W. H. Song, J. M. Dai. 2009-03-12. Anisotropic, Intermediate Coupling Superconductivity in Cu0.03TaS2. https://doi.org/10.1088/0953-8984%2F21%2F14%2F145701

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