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arXiv · 0910.5006

Calorimetric Evidence of Multiband Superconductivity in Ba(Fe0.925Co0.075)2As2

F. Hardy·T. Wolf·R. A. Fisher·R. Eder·P. Schweiss·P. Adelmann·H. v. Loehneysen·C. Meingast
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Abstract

We report on the determination of the electronic heat capacity of a slightly overdoped (x = 0.075) Ba(Fe1-xCox)2As2 single crystal with a Tc of 21.4 K. Our analysis of the temperature dependence of the superconducting-state specific heat provides strong evidence for a two-band s-wave order parameter with gap amplitudes 2D1(0)/kBTc=1.9 and 2D2(0)/kBTc=4.4. Our result is consistent with the recently predicted s+- order parameter [I. I. Mazin et al., Phys. Rev. Lett. 101, 057003 (2008)].

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F. Hardy, T. Wolf, R. A. Fisher, R. Eder, P. Schweiss, P. Adelmann, H. v. Loehneysen, C. Meingast. 2009-10-26. Calorimetric Evidence of Multiband Superconductivity in Ba(Fe0.925Co0.075)2As2. https://doi.org/10.1103/physrevb.81.060501

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