摘要
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.
基金
the financial supports from the National Natural Science Foundation of China (11474339)
the National Basic Research Program of China (2010CB923000 and 2011CBA00100)
the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB07020100)