Superconductivity at 7.8 K in the ternary LaRu2As2 compound

Here we report the discovery of superconductivity in the ternary LaRu_2As_2 compound. The polycrystalline LaRu_2As_2 samples were synthesized by the conventional solid state reaction method. Powder X-ray diffraction analysis indicates that LaRu_2As_2 crystallizes in the Th Cr_2Si_2-type crystal structure with the space group I4/mmm(No. 139), and the refined lattice parameters are a = 4.182(6)  and c = 10.590(3) . The temperature dependent resistivity measurement shows a clear superconducting transition with the onset T_c(critical temperature) at 7.8 K, and zero resistivity happens at 6.8 K. The upper critical field at zero temperature μ_0H_(c2)(0) was estimated to be 1.6 T from the resistivity measurement. DC magnetic susceptibility measurement shows a bulk superconducting Meissner transition at 7.0 K, and the isothermal magnetization measurement indicates that LaRu_2As_2 is a type-II superconductor.

Here we report the discovery of superconductivity in the ternary LaRu2As2 compound. The polycrystalline LaRu2As2 samples were synthesized by the conventional solid state reaction method. Powder X-ray diffraction analysis indicates that LaRu2As2 crystallizes in the ThCr2Si2-type crystal structure with the space group 14/ mmm （No. 139）, and the refined lattice parameters are a = 4.182（6）A and c = 10.590（3）A. The temperature dependent resistivity measurement shows a clear superconducting transition with the onset Tc （critical tempera- ture） at 7.8 K, and zero resistivity happens at 6.8 K. The upper critical field at zero temperature μ0Hc2（0） was estimated to be 1.6 T from the resistivity measurement. DC magnetic susceptibility measurement shows a bulk superconducting Meissner transition at 7.0 K, and the isothermal magnetization measurement indicates that LaRu2As2 is a type-II superconductor.