Title: Fabrication of grain boundary junctions using NdFeAs(O,F) superconducting thin films,
Abstract: We report on the growth of NdFeAs(O,F) thin films on [001]-tilt MgO bicrystal
substrates with misorientation angle theta_GB=6°, 12°, 24° and
45°, and their inter- and intra-grain transport properties. X-ray
diffraction study confirmed that all our NdFeAs(O,F) films are epitaxially
grown on the MgO bicrystals. The theta_GB dependence of the inter-grain
critical current density Jc shows that, unlike Co-doped BaFe2As2 and Fe(Se,Te),
its decay with theta_GB is rather significant. As a possible reason of this
result, fluorine may have diffused preferentially to the grain boundary region
and eroded the crystal structure.