Method of forming weak-link Josephson junction, and superconducting device employing the junction

摘要

A weak-link Josephson junction is of the type employing a thin film of an oxide superconductor, in which a crystal grain boundary produced reflecting an artificial crystal defect is utilized as the weak- link junction. The crystal grain boundary is formed concretely by a method in which atoms of different species are deposited on the predetermined part of the surface of a substrate, the predetermined part of the surface of a substrate is disturbed, or parts of different crystal face orientations are formed at the surface of a substrate, whereupon the superconducting thin film is epitaxially grown on the substrate, or by a method in which the predetermined part of the superconducting thin film, epitaxially grown on a substrate, is diffused with atoms of different species hampering a superconductivity, or the predetermined part of the superconducting thin film is disturbed, whereupon the superconducting thin film is annealed.