Three-dimensional superconductivity and vortex glass transition in La1.87Y0.13CuO4

The angular dependence of the critical current density (J c (θ)) and the vortex glass transition temperature (Tg(θ)) in La 1.87 Y 0.13 CuO 4 were measured at different fields and temperatures. Both J c (θ) and T g (θ) showed a strong angular variation, which is typical for anisotropic superconductors. The angular variation could be described by using the anisotropic three-dimensional Ginzburg-Landau theory. From our analysis, we were able to estimate the anisotropy ratio.