Multilayer distorted-lattice copper-oxide perovskite structures including NdCeCuO and YBaCuO multi-layers

摘要

The present invention concerns a multilayered structure comprising copper-oxide perovskite material having strained crystallographic lattices and altered superconductive properties. The multilayer structure of the invention comprises at least one first layer of a first copper-oxide material and at least one second layer of a second, different copper-oxide perovskite material. The first and second layers are adjacent to one another in an epitaxial lattice-distortion relationship. The first and second copper-oxide perovskite materials in unstressed bulk states define respectively first and second comparison nondistorted crystallographic lattice structures. The first and second comparison nondistorted crystallographic lattice structures have unit cell dimensions which differ in at least one dimension. The first copper-oxide perovskite material in the first layer has a first crystallographic lattice structure which is distorted relative to the first comparison nondistorted crystallographic lattice structure. The second copper-oxide perovskite material in the second layer has a second crystallographic lattice structure which is distorted relative to the second comparison nondistorted crystallographic lattice structure. The first copper-oxide perovskite material in at least one first layer exhibits normal and superconductive states which define a set of normal/superconducting transition parameters. At least one of the normal/superconducting transition parameters differs from a corresponding comparison normal/superconducting transition parameter for the first copper-oxide perovskite material in the unstressed bulk state.