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arXiv · 1403.0191

Heat transport in RbFe2As2 single crystal: evidence for nodal superconducting gap

Z. Zhang·A. F. Wang·X. C. Hong·J. Zhang·B. Y. Pan·J. Pan·Y. Xu·X. G. Luo·X. H. Chen·S. Y. Li
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Abstract

The in-plane thermal conductivity of iron-based superconductor RbFe$_2$As$_2$ single crystal ($T_c \approx$ 2.1 K) was measured down to 100 mK. In zero field, the observation of a significant residual linear term $\kappa_0/T$ = 0.65 mW K$^{-2}$ cm$^{-1}$ provides clear evidence for nodal superdonducting gap. The field dependence of $\kappa_0/T$ is similar to that of its sister compound CsFe$_2$As$_2$ with comparable residual resistivity $\rho_0$, and lies between the dirty and clean KFe$_2$As$_2$. These results suggest that the (K,Rb,Cs)Fe$_2$As$_2$ serial superconductors have a common nodal gap structure.

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Z. Zhang, A. F. Wang, X. C. Hong, J. Zhang, B. Y. Pan, J. Pan, Y. Xu, X. G. Luo, X. H. Chen, S. Y. Li. 2014-03-02. Heat transport in RbFe2As2 single crystal: evidence for nodal superconducting gap. https://doi.org/10.1103/physrevb.91.024502

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