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A series of quasimultilayers consisting of YBa2Cu3O7-δ (YBCO) and SrRuO3 (SRO), namely, p×(YBCO(m)/SRO(n)) (p: repetition periods; m: YBCO pulse number; n: SRO pulse number), is prepared on single crystal SrTiO3 by pulsed laser deposition. X-ray diffraction measurements reveal that a heterogeneous phase of Ba2YRuO6 is formed due to the chemical reaction, while both the in-plane and out-of-plane textures of the present quasimultilayers are as good as in the pure YBCO films. The content of Ba2YRuO6 increases as the pulse number of SRO increases, leading to the decrease in superconducting transition temperature (Tc). There is no obvious difference in Tc between the samples with the different deposition sequence orders of YBCO and SRO. The magnetic field dependence of critical current density (Jc) shows an enhanced flux pinning at relatively high fields for all the present quasimultilayers, which occurs at different ranges of fields depending on the applied temperatures. The Jc of the quasimultilayers can reach two times higher than that of pure YBCO films in a wide range of magnetic fields, which shows the promising application for coated conductors. [ABSTRACT FROM AUTHOR]

YBa2Cu3O7-δ (YBCO) films are prepared on the substrate of single crystal LaAlO3 (LAO) by using metal trifluoroacetates deposition (TFA-MOD). The phase evolvement, magneto-transport and flux pinning characteristics in MOD-YBCO films are studied. It is revealed that Ba-Cu-O and Y-Cu-O precipitates are formed and can be controlled by optimum crystallization process. The field dependence of Jc (H//c) shows that the accommodation field Hacc decreases exponentially with increasing temperature and the power-law relationship holds in the medium fields with an exponent α of about 0.67, nearly independent of temperatures. Compared with the samples grown by pulsed laser deposition, MOD films have larger Hacc at higher temperatures (> 50 K) indicating that the value of the exponent α is affected by the precipitates entrapped in the YBCO matrix. [ABSTRACT FROM AUTHOR]

Abstract: The / La0.88Ca0.12MnO3 (YBCO/LCMOi) and / La0.33Ca0.67MnO3 (YBCO/LCMOj) bilayers are fabricated with the method of pulsed laser deposition, and the magnetic dependent proximity effects are investigated. The magnetic fields were applied parallel (in-plane) and perpendicular (out-of-plane) to the film plane. Magnetic properties curves in different temperature range and magnetic field along two crystal orientation show a complex behavior due to the interplay between Meissner currents in YBCO layer and the magnetic fields present in LCMOi (or LCMOj) layer. Ac susceptibility measurements show that the suppression of superconductivity in LCMOi and LCMOj bilayers. The obtained results are discussed in terms of the effect of hole charge transfer from YBCO to LCMOi (or LCMOj) on the proximity between superconductivity and ferromagnetism. [Copyright &y& Elsevier]