Patent ID: 7723616

Claim:
A superconducting cable including a plurality of cable cores that are twisted together, each cable core having a superconducting layer and an insulating layer; the superconducting cable comprising: (a) a first core having a first superconducting layer; and (b) a second core having a second superconducting layer that has an inner diameter larger than the outer diameter of the first superconducting layer, wherein the first and second superconducting layers each include helically wound tape-shaped wires having a structure in which a plurality of filaments made of a superconducting material are configured in a matrix such as a silver sheath, wherein the first core includes no additional superconducting layer made of a superconducting material other than the first superconducting layer, and wherein the second core includes no additional superconducting layer made of a superconducting material other than the second superconducting layer.