Biaxially textured cobalt-doped BaFe2As2 films with high critical current density over 1 MA/cm2 on MgO-buffered metal-tape flexible substrates

Abstract

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 (ΔϕBaFe2As2:Co) of ∼3° regardless of twice larger misorientations of the MgO base-layers (ΔϕMgO=7.3°), 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.