2010 Volume 51 Issue 2 Pages 227-230
A series of single-phased La(Pt1−xAux)4Ge12 compounds were prepared by an arc-melting method. The crystal structure and basic superconductivity parameters have been systematically investigated by X-ray diffraction and by examining the temperature and field dependences of electrical resistivity, magnetization and heat capacity. The lattice parameter a increases and the superconducting transition temperature Tc decreases gradually with increasing Au content x. The low critical field Hc1(T) and the upper critical field Hc2(T) were estimated from the isothermal magnetization (M-H-T) and electrical transport (ρ-H-T) measurements, respectively. The evaluated Hc1(0) and Hc2(0) indicate a decrease tendency with increasing x, and enable us to deduce the coherence length ξ(0), penetration depth λ(0), Ginzburg-Landau parameter κ(0) and thermodynamic critical field Hc(0). The present results are compared with those of the related systems.