Abstract: An oxide superconducting multilayered thin film structure having a laminated layer structure of oxide superconductor thin film layers and non-superconductor thin film layers constituted by a combination of material groups for making strain free interfaces among both thin film layers. For example, an oxide superconductor multilayered film constituted by a laminated layer structure where thin films of an oxide superconductor represented by the chemical formula of M'Ba.sub.2 Cu.sub.3 O.sub.7-.delta. (M'; a rare earth element of Nd, Sm, Eu or the like or an alloy of these, .delta.; oxygen depletion amount) and thin films of an oxide represented by the chemical formula of M*Ba.sub.2 Cu.sub.3 O.sub.7-.delta. (M*; an element of Pr, Sc or the like or an alloy of these, .delta.; oxygen depletion amount) are alternately stacked. The oxide thin films are thin films fabricated by a pulsed laser deposition process or a sputtering process. A Josephson device can be provided by using the multilayered film.

Abstract: A single crystal material is prepared by forming a layer of an amorphous substance over a surface of a substrate of a single crystal having the same chemical composition as that of the amorphous substance, the resulting composite material is heated to epitaxially grow the amorphous layer into a single crystal layer. A composite material for producing such a single crystal material is also disclosed which includes a substrate of a single crystal, and a layer of an amorphous substance having the same chemical composition as that of the substrate, the layer having such a thickness that the layer as a whole can epitaxially grow to make a single crystal layer.