(Ba,La)CuO_2/CaCuO_2 superconducting multilayers: stabilizing effect of La

摘要

Superconducting multilayers, whose growth and structure are determined by the kinetic deposition instead of by thermodynamics, are a powerful tool for investigating high T_c superconductor properties. By means of pulsed laser deposition, we grew ((Ba, La)CuO_(2+δ))_2/(CaCuO_2)_n superconducting superlattices. Different electrical properties have been observed by increasing La doping in the block layer: in particular, 15%-La substituted samples showed a good metallic behavior in the normal state, underwent a superconducting transition at 70 K and presented a low anisotropy, similar to that of YBCO.