Superconductivity in the surface layer of SrTiO3/(Ba0.9Nd0.1)CuO2+x/CaCuO2 heteroepitaxial structures

We report on the pulsed laser deposition and characterization of the (BaCuO(2))(m)/(CaCuO(2))(n) heterostructures deposited on to SrTiO(3) (001) substrates. For some of the heterostructures realized it was possible to find a high temperature superconducting transition. These thin films represent one of the simplest structures containing the two structural subunits constituting all the existing high temperature cuprate superconductors. We studied the superconducting properties of these thin films with m varying between 2 and 5 and n varying between 0.66 and 6. We discuss the results also in comparison with those obtained for the superconducting BaCuO(2)/CaCuO(2) superlattices. The results obtained can offer new possibilities to study the fundamental physical mechanism of high temperature superconductivity.