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Thin YBa2Cu3O6+x (YBCO) films are prepared by pulsed laser deposition (PLD) from pure micro- (μ) and nanocrystalline (n) targets and a n-target optimally doped with 3.9 wt% BaZrO3 (BZO). Effects of target grain size and doping on superconducting (SC) properties of the films are investigated using a SQUID magnetometer up to 5 T and transport measurements in pulsed magnetic fields up to 30 T. In comparison with μ-films, clearly increased values of jc are observed in n-films. Optimal doping with BZO still increases this difference in high magnetic field range and lengthens the low-field plateau of jc(B) and increases the accommodation field B* which are typically around 110 mT, 160 mT and 500 mT at 5 K in μ, n- and BZO-doped films, respectively. Transport measurements at T > 65 K show significant improvement of irreversibility line (IRL) and jc(B) in films prepared from n-target and BZO-doped target. These improvements of the superconducting properties in high magnetic fields make pure and BZO-doped n-films attractive for high field applications. [ABSTRACT FROM AUTHOR]

We report on magnetic-field dependences of Hall coefficient and resistivity for InN films grown by plasma-assisted molecular beam epitaxy. The Hall coefficient rises with the magnetic field. This anomalous behavior is discussed in terms of the presence of highly conducting inhomogeneities in the films. According to the magnetic field and temperature dependences of the film resistivity, the inhomogeneities are attributed to metallic indium nanoparticles formed presumably around extended defects within the InN epilayers, at their surface and the InN/GaN interface. Good correlation is observed between the growth conditions of the InN films and their electrical properties recalculated using the model. [ABSTRACT FROM AUTHOR]