%0 Journal Article
%T Nodal gap in iron-based superconductor CsFe$_2$As$_2$ probed by quasiparticle heat transport
%A X. C. Hong
%A X. L. Li
%A B. Y. Pan
%A L. P. He
%A A. F. Wang
%A X. G. Luo
%A X. H. Chen
%A S. Y. Li
%J Physics
%D 2013
%I arXiv
%R 10.1103/PhysRevB.87.144502
%X The thermal conductivity of iron-based superconductor CsFe$_2$As$_2$ single crystal ($T_c =$ 1.81 K) was measured down to 50 mK. A significant residual linear term $\kappa_0/T$ = 1.27 mW K$^{-2}$ cm$^{-1}$ is observed in zero magnetic field, which is about 1/10 of the normal-state value in upper critical field $H_{c2}$. In low magnetic field, $\kappa_0/T$ increases rapidly with field. The overall field dependence of $\kappa_0/T$ for our CsFe$_2$As$_2$ (with residual resistivity $\rho_0$ = 1.80 $\mu\Omega$ cm) lies between the dirty KFe$_2$As$_2$ (with $\rho_0$ = 3.32 $\mu\Omega$ cm) and the clean KFe$_2$As$_2$ (with $\rho_0$ = 0.21 $\mu\Omega$ cm). These results strongly suggest nodal superconducting gap in CsFe$_2$As$_2$, similar to its sister compound KFe$_2$As$_2$.
%U http://arxiv.org/abs/1302.2300v2