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arXiv · 1109.3135

Calorimetric study of the superconducting and normal state properties of Ca(Fe1-xCox)2As2

M. Abdel-Hafiez·L. Harnagea·S. Singh·U. Stockert·S. Wurmehl·R. Klingeler·A. U. B. Wolter·B. Buechner
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Abstract

We present a calorimetric study on single crystals of Ca(Fe1-xCox)2As2 (x = 0, 0.032, 0.051, 0.056, 0.063, and 0.146). The combined first order spin-density wave/structural transition occurs in the parent CaFe2As2 compound at 168 K and gradually shifts to lower temperature for low doping levels (x = 0.032 and x = 0.051). It is completely suppressed upon higher doping x = 0.056. Simultaneously, superconductivity appears at lower temperature with a transition temperature around Tc = 14.1 K for Ca(Fe0.937Co0.063)2As2. The phase diagram of Ca(Fe0.937Co0.063)2As2 has been derived and the upper critical field is found to be H(c) c2 = 11.5

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M. Abdel-Hafiez, L. Harnagea, S. Singh, U. Stockert, S. Wurmehl, R. Klingeler, A. U. B. Wolter, B. Buechner. 2011-09-14. Calorimetric study of the superconducting and normal state properties of Ca(Fe1-xCox)2As2. https://doi.org/10.1088/1742-6596/391/1/012120

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