Abstract: A method and an apparatus are provided by which a high temperature superconductor can be cooled to a lower temperature easily and conveniently at a low cost. In the cooling method and apparatus according to the present invention, a high temperature superconductor constituting a cable (50) is cooled by liquid refrigerant (41). The refrigerant (41) is cooled by a refrigerator (10) to or below the freezing point which is given by the refrigerant having a stationary state in the cooling system. The cooled refrigerant is forced to flow and circulated by a pump (34), and such a physical action maintains the refrigerant in a fluid state at a temperature equal to or lower than the freezing point. A viscometer (61) may be used to measure the viscosity of the refrigerant to modulate the flow rate of the refrigerant according to the measured viscosity. According to the present invention, liquid nitrogen is maintained in a fluid state at approximately 45 K, for example.

Abstract: An oxide superconducting element wire (20) comprises a base material (1), an intermediate layer (2), and an oxide superconducting thin film (3). The base material (1) being long and flexible has a cross-section in a circular or a regular polygonal form perpendicular to the longitudinal direction of the same. The periphery of the base material (1) is covered with an intermediate layer (2) and the periphery of the same is covered with an oxide superconducting thin film (3). The oxide superconducting thin film (3) has a portion in which a crystal orientation is three-axes aligned continuing in the longitudinal direction of the element wire (20).

Abstract: An oxide superconducting element wire (20) comprises a base material (1), an intermediate layer (2), and an oxide superconducting thin film (3). The base material (1) being long and flexible has a cross-section in a circular or a regular polygonal form perpendicular to the longitudinal direction of the same. The periphery of the base material (1) is covered with an intermediate layer (2) and the periphery of the same is covered with an oxide superconducting thin film (3). The oxide superconducting thin film (3) has a portion in which a crystal orientation is three-axes aligned continuing in the longitudinal direction of the element wire (20).