Critical current density of strained multilayer thin films of Nd1.83Ce0.17CuOx/YBa2Cu3O7−δ

Abstract
The superconducting transport properties of strained multilayer thin films of YBa2Cu3O7−δ/ Nd1.83Ce0.17CuOx, grown heteroepitaxially by laser ablation deposition, are reported. For individual layer thicknesses below a critical layer thickness of about 250 Å, coherency strain removes the orthorhombic distortion in the YBa2Cu3O7−δ layers and makes them twin‐free. Zero‐field critical current densities as high as 1.1×107 A/cm2 at 77 K have been measured for the YBa2Cu3O7−δ layers. Flux pinning energies at zero temperature and zero magnetic field in the range of 80–140 meV have been found.