Search

Abstract: We report the laser-induced voltage (LIV) effects in c-axis oriented Bi2Sr2Co2O y thin films grown on (001) LaAlO3 substrates with the title angle α of 0°, 3°, 5° and 10° by a simple chemical solution deposition method. A large open-circuit voltage with the sensitivity of 300mV/mJ is observed for the film on 10° tilting LaAlO3 under a 308nm irradiation with the pulse duration of 25ns. When the film surface is irradiated by a 355nm pulsed laser of 25ps duration, a fast response with the rise time of 700ps and the full width at half maximum of 1.5ns is achieved. In addition, the experimental results reveal that the amplitude of the voltage signal is approximately proportional to sin2α and the signal polarity is reversed when the film is irradiated from the substrate side rather than the film side, which suggests the LIV effects in Bi2Sr2Co2O y thin films originate from the anisotropic Seebeck coefficient of this material. [ABSTRACT FROM AUTHOR]

Abstract: The CeO2 cap layer were deposited on yttria-stabilized zirconia (YSZ)/Y2O3 buffered Ni–5at.%W (Ni–W) substrate by direct-current magnetron reactive sputtering for YBa2Cu3O7−δ (YBCO) coated conductors. Morphology evolvements of CeO2 cap layers on the substrate temperature and deposition rate were investigated. Atomic force microscope exhibited the grain shape grown from granule to cluster with the temperature increasing, the grain size decreased as the sputter power increased, and their mechanisms were proposed. The root mean square surface roughness of the best sample was 1.8nm over a 3μm×3μm area. Moreover, YBCO films deposited on the CeO2/YSZ/Y2O3 buffered Ni–W substrates using pulsed laser deposition (PLD) achieved the critical current density J c of about 1.72MA/cm2 at 77K and self field. [Copyright &y& Elsevier]