High quality c^-axis oriented thin and ultra-thin films have been grown in situ on (100) surfaces of ZrO?, SrTiO, and MgO. Sharp transitions were observed with T,,,,,, of 87-91 K for films thicker than 70 A. On atomically polished MgO substrates films as thin as 15 A revealed a full transition to superconductivity above 45.5 K. The critical current density at 77 K was found to be strongly depen...

We report a detailed study of the grain orientations and grain boundary (GB) networks in Y2O3 films grown on Ni-5 at.%W substrates. Electron back scatter diffraction (EBSD) exhibited different GB misorientation angle distributions, strongly decided by Y2O3 films with different textures. The subsequent yttria-stabilized zirconia (YSZ) barrier and CeO2 cap layer were deposited on Y2O3 layers by r...

Motivated by recent pump-probe experiments indicating enhanced coherent c-axis transport in underdoped YBCO, we study Josephson junctions periodically driven by optical pulses. We propose a mechanism for this observation by demonstrating that a parametrically driven Josephson junction shows an enhanced imaginary part of the low-frequency conductivity when the driving frequency is above the plas...

A very smooth surface film of c-axis oriented Y B a z C w G (YBCO) with roughness of less than monomolecular layer over lOpmxlO~rn, free of precipitates, has been obtained by atomic layer-by-layer metalorganic chemical vapor deposition (MOCVD) on a SrTi03 substrate at 650°C. A very large terrace length of 0.3-0.5pm may be due to the enhanced migration of growing species on the surface. The resu...

The structure of CeO2 films grown on (1102) sapphire and on YBCO thin films was investigated. The films reported on here were grown by pulsed excimer laser deposition and their surface structure was probed using atomic force microscopy. We found that CeO2 films grown on sapphire were epitaxial with a granular structure which is smooth on an atomic scale. We see evidence of a surface reconstruct...

Lanthanum zirconate (LZO) films from water-based precursors were deposited on Ni-5%W tape by chemical solution deposition. The buffer capacity of these layers includes the prevention of Ni oxidation of the substrate and Ni penetration towards the YBCO film which is detrimental for the superconducting properties. X-ray Photoelectron Spectroscopy depth profiling was used to study the barrier effi...

In this study, High temperature superconductor YBa2Cu3O7-x (YBCO) nanoparticle was prepared by Sol-gel technique. The sol-gel includes a homogeneous solution of Y-Ba-Cu acetate precursor and acetic acid. powder compressed hydraulic at 5 ton/cm2 needed post-reaction heat treatment 850 °C for 8 h with oxygen flow. YBCO bulk has been characterized using traditional R-T measurements, producing best...