The present invention is a superconducting wire including: a wire formed of a superconducting material; and a superconducting stabilization material disposed in contact with the wire, in which the superconducting stabilization material is formed of a copper material which contains: one or more types of additive elements selected from Ca, Sr, Ba, and rare earth elements in a total of 3 ppm by mass to 400 ppm by mass; a balance being Cu and inevitable impurities, and in which a total concentration of the inevitable impurities excluding O, H, C, N, and S which are gas components is 5 ppm by mass to 100 ppm by mass.

The present invention is a superconducting wire including: a wire formed of a superconducting material; and a superconducting stabilization material disposed in contact with the wire, in which the superconducting stabilization material is formed of a copper material which contains: one or more types of additive elements selected from Ca, Sr, Ba, and rare earth elements in a total of 3 ppm by mass to 400 ppm by mass; a balance being Cu and inevitable impurities, and in which a total concentration of the inevitable impurities excluding O, H, C, N, and S which are gas components is 5 ppm by mass to 100 ppm by mass.

A superconducting coil comprising an oxide superconducting wire includes: a superconducting laminate comprising a substrate and an oxide superconducting layer; and a stabilization layer made of copper plating formed around the superconducting laminate. A thickness d of the stabilization layer is in the range of 10 to 40 μm. A ratio Ra/d of the thickness d of the stabilization layer and an arithmetic mean roughness Ra of an outer surface of the stabilization layer is in the range of 0.005 to 0.03. An intermediate layer is arranged between the substrate and the oxide superconducting layer. When a tensile test of pulling the oxide superconducting wire in a longitudinal direction within a stress range of 180 to 600 MPa in liquid nitrogen is performed, a ratio of a critical current when a repeated pulling number reaches 100,000 times and an initial critical current measured before the tensile test is 0.99 or more.

A superconducting coil comprising an oxide superconducting wire includes: a superconducting laminate comprising a substrate and an oxide superconducting layer; and a stabilization layer made of copper plating formed around the superconducting laminate. A thickness d of the stabilization layer is in the range of 10 to 40 μm. A ratio Ra/d of the thickness d of the stabilization layer and an arithmetic mean roughness Ra of an outer surface of the stabilization layer is in the range of 0.005 to 0.03. An intermediate layer is arranged between the substrate and the oxide superconducting layer. When a tensile test of pulling the oxide superconducting wire in a longitudinal direction within a stress range of 180 to 600 MPa in liquid nitrogen is performed, a ratio of a critical current when a repeated pulling number reaches 100,000 times and an initial critical current measured before the tensile test is 0.99 or more.

A precursor for Nb.sub.3Sn single-core superconducting wire includes a Sn-based wire rod, a first Cu-based tube covering an outer circumferential surface of the Sn-based wire rod, an Nb-based tube covering an outer surface of the first Cu-based tube, and a second Cu-based tube covering an outer surface of the Nb-based tube. The Sn-based wire rod contains a matrix phase and at least one kind of hard phases that is harder than the matrix phase. In a cross section parallel to a longitudinal direction of the precursor for Nb.sub.3Sn single-core superconducting wire, a maximum dimension of the hard phases in a width direction perpendicular to the longitudinal direction is 50% or less of a minimum dimension in the width direction of the Sn-based wire rod and/or is equal to or smaller than a minimum thickness in the width direction of the Nb-based tube.

A precursor for Nb.sub.3Sn single-core superconducting wire includes a Sn-based wire rod, a first Cu-based tube covering an outer circumferential surface of the Sn-based wire rod, an Nb-based tube covering an outer surface of the first Cu-based tube, and a second Cu-based tube covering an outer surface of the Nb-based tube. The Sn-based wire rod contains a matrix phase and at least one kind of hard phases that is harder than the matrix phase. In a cross section parallel to a longitudinal direction of the precursor for Nb.sub.3Sn single-core superconducting wire, a maximum dimension of the hard phases in a width direction perpendicular to the longitudinal direction is 50% or less of a minimum dimension in the width direction of the Sn-based wire rod and/or is equal to or smaller than a minimum thickness in the width direction of the Nb-based tube.

The superconducting coil includes: a winding frame; and at least two superconducting rectangular wire layers provided in such a manner that a superconducting rectangular wire is spirally wound on an outer surface of the frame such that wires adjacent to each other in an axial direction of the frame are arranged side by side and separated, the wire including an NbTi-based or Nb.sub.3Sn-based wire having a surface coated with copper or copper alloy, in which at least a thermoplastic fusible resin is provided in a separated section between the adjacent wires, and when viewed in a cross section including an axis of the frame, at least one of voids that are partitionable on outer surfaces of a total of three wires and a total of four wires located on the two adjacent layers and adjacent to each other are 4% or less in terms of a void ratio (V1).

A superconducting power cable system includes a superconducting power cable in a first temperature environment separated from a second temperature environment by a thermal barrier. The first temperature environment is an interior of a cryostat and is at a lower temperature than the second temperature environment located outside of the cryostat. At least one superconducting feeder cable has a first end electrically coupled to the superconducting power cable in the first temperature environment, and a second end electrically coupled to a normal conducting current lead in the second temperature environment. Each superconducting feeder cable is a flexible superconducting cable or wire formed of multiple superconducting tapes that are wound in a helical fashion and in multiple layers around a round former.

A superconducting power cable system includes a superconducting power cable in a first temperature environment separated from a second temperature environment by a thermal barrier. The first temperature environment is an interior of a cryostat and is at a lower temperature than the second temperature environment located outside of the cryostat. At least one superconducting feeder cable has a first end electrically coupled to the superconducting power cable in the first temperature environment, and a second end electrically coupled to a normal conducting current lead in the second temperature environment. Each superconducting feeder cable is a flexible superconducting cable or wire formed of multiple superconducting tapes that are wound in a helical fashion and in multiple layers around a round former.

The present disclosure relates to routing superconducting wires in superconducting circuits and in particular to efficiently routing superconducting wires that meet inductance requirements. The superconducting wire routing technique involves modeling the target location not only as a physical location, but as a physical location (e.g., x, y, and z dimensions) combined with inductance (e.g., a target inductance range). One or more other constraints may also be included in the modeling, such as a number of wires that would need to be moved/lifted, a number of circuit-vias allowing passage through layers of the circuit, an amount of cross-coupling with other inductors, and a number of wire segments.