  High critical current densities (Jc) > 1 MA/cm2 were realized in cobalt-doped
BaFe2As2 (BaFe2As2:Co) films on flexible metal substrates with
biaxially-textured MgO base-layers fabricated by an ion-beam assisted
deposition technique. The BaFe2As2:Co films showed small in-plane crystalline
misorientations (delta fai BaFe2As2:Co) of ~3o regardless of doubly larger
misorientaions of the MgO base-layers (delta fai MgO = 7.3o), and exhibited
high self-field Jc up to 3.5 MA/cm2 at 2 K. These values are comparable to that
on MgO single crystals and the highest Jc among iron pnictide superconducting
tapes and wires ever reported. High in-field Jc suggests the existence of
c-axis correlated vortex pinning centers.
