Superconducting properties of single-crystalline Ca(Al0.5,Si0.5)2:: A ternary silicide with the AlB2-type structure -: art. no. 064512

Superconducting properties of single-crystalline Ca(Al-0.5,Si-0.5)(2), which is isostructural to MgB2, were studied by measurements of electrical resistivity, Hall coefficient, and magnetization. Ca(Al-0.5,Si-0.5)(2) is a type-II superconductor with a carrier density of 8.6x10(26) electrons/m(3) at 290 K. The lower critical field H-C1 has a parabolic temperature dependence typical for conventional superconductors. The upper critical field (H-C2) anisotropy ratio has a temperature-independent value of 2.3. The Ginzburg-Landau (GL) parameter kappa(0) is equal to 12 and 5.2 in the ab-plane and c-axis directions, respectively. The anisotropy of the critical fields can be well described by the anisotropic GL theory.