Publication Type:Conference Paper
Source:Proceedings of SPIE - The International Society for Optical Engineering, Publ by Int Soc for Optical Engineering, Bellingham, WA, United States, Volume 1597, p.101-107 (1992)
Keywords:copper oxides, heterostructures, High temperature superconductors, Laser Beams–Applications, pulsed laser deposition, Transport properties, Yttrium barium copper oxides, yttrium compounds
We have investigated the influence of interface effects and CuO2 plane orientation on transport properties of high temperature superconducting (HTS) thin films in YBa2 Cu3O7-PrBa2Cu3O7 (YBCO-PrBCO) heterostructures grown by pulsed laser deposition. Two unit cell (≈ 24 angstroms) thick YBCO films, isolated in c-axis oriented PrBCO/YBCO/PrBCO trilayers, are found to superconduct at temperatures above 20 K, while films thicker than 6 unit cells display bulk superconducting properties. An epitaxial process has also been developed to grow YBCO films and YBCO/PrBCO heterostructures with the CuO2 planes oriented normal to the film surface. These a-axis oriented films display transport properties comparable to the best c-axis oriented films and, moreover, are better suited to the fabrication of sandwich-type Josephson junction devices by virtue of the longer superconductive coherence length normal to the direction of the YBCO-PrBCO barrier interface.
cited By 0