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    Combinatorial synthesis of (YxGd1-x)Ba2Cu3Ox superconducting thin films
    (Amsterdam [u.a.] : Elsevier, 2012) Kirchner, A.; Erbe, M.; Freudenberg, T.; Hühne, R.; Feys, J.; Van Driessche, I.; Schultz, L.; Holzapfel, B.
    Environmentally friendly water-based YBa2Cu3Ox (YBCO) and GdBa2Cu3Ox (GdBCO) precursor solutions were synthesized to realize thin films by chemical solution deposition. Pure YBCO and GdBCO precursor solutions were used for ink plotting on SrTiO3 substrates and subsequent thermal treatment at the corresponding crystallization temperature. Phase formation of Gd123 requires a higher crystallization temperature of 840 °C compared to the Y123 phase. The critical temperature of YBCO films is about 92 K with a sharp transition into the superconducting state. Micro liter sized ink volumes of YBCO and GdBCO were successfully mixed for two-dimensional ink plotting of a (YxGd1-x)Ba2Cu3Ox film library. A homogeneous surface and no indication of a-axis growth were found in all mixed films.
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    Superconductivity in multi-phase Mg-B-O compounds
    (Amsterdam [u.a.] : Elsevier, 2012) Prikhna, T.; Gawalek, W.; Eisterer, M.; Weber, H.W.; Noudem, J.; Sokolovsky, V.; Chaud, X.; Moshchil, V.; Karpets, M.; Kovylaev, V.; Borimskiy, A.; Tkach, V.; Kozyrev, A.; Kuznietsov, R.; Dellith, J.; Shmidt, C.; Basyuk, T.; Litzkendorf, D.; Karau, F.; Dittrich, U.; Tomsic, M.
    Structures of MgB2-based materials manufactured under pressure (up to 2 GPa) by different methods having high superconducting performance and connectivity are multiphase and contain different Mg-B-O compounds. Some oxygen can be incorporated into MgB2 and boron into MgO structures, MgBx (X=4-20) inclusions contain practically no oxygen. Regulating manufacturing temperature, pressure, introducing additions one can influence oxygen and boron distribution in the materials and thus, affect the formation, amount and sizes of Mg-B-O and MgBx inclusions and changing type of pinning, pinning force and so affect critical current density jc. The boron concentration increase in initial Mg and B mixture allows obtaining sample containing 88.5 wt% of MgB12 with Tc of 37.4 K (estimated magnetically).
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    A superconducting levitation transport model system for dynamical and didactical studies
    (Amsterdam [u.a.] : Elsevier, 2012) Rosenzweig, St.; Reich, E.; Neu, V.; Berger, D.; Peukert, K.; Holzapfel, B.; Schultz, L.; Pospiech, G.
    Superconducting levitation transport systems might become very attractive in the near future due to various reasons. The realisation of contactless systems allows e.g. extended maintenance-free operation with high efficiency since such a system only needs energy for cooling and propulsion. We established a small superconducting levitation transport model system called "SupraTrans Mini" consisting of permanent magnetic rails and a levitated vehicle including four YBCO-bulk samples in a cryostat. The rail system consists of an oval shaped loop (2.90 m x 1.44 m), which was build up from individual linear and curved track modules. Inside the vehicle position variations of the superconductors are possible. By means of velocity, acceleration and temperature measurements different dynamical aspects of our complex levitation system can be investigated. We also show the broad applicability of the experimental setup for didactical studies in physics.
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    Josephson and tunneling junctions with thin films of iron based superconductors
    (Amsterdam [u.a.] : Elsevier, 2012) Schmidt, S.; Döring, S.; Tympel, V.; Schmidl, F.; Haindl, S.; Iida, K.; Holzapfel, B.; Seidel, P.
    We produced planar hybrid Superconductor - Normal metal - Superconductor (SNS') junctions and interfaceengineered edge junctions (SN'S' or SIS' with normal metal (N') or insulating (I) barrier) with various areas using Co-doped Ba-122 as base electrode. Varying the thickness of the Normal metal (gold) barrier of the planar junctions, we can either observe Josephson behavior at thinner gold thicknesses or transport dominated by Andreev reflection. The edge junctions seem to form a SN'S'-contact.