An MgB.sub.2 superconducting wire includes a core containing MgB.sub.2 and a metal sheath which surrounds the core. The core includes at least a first MgB.sub.2 core positioned on the center side, and a second MgB.sub.2 core positioned outside the first MgB.sub.2 core, and the density of the second MgB.sub.2 core is lower than the density of the first MgB.sub.2 core.

An MgB.sub.2 superconducting wire includes a core containing MgB.sub.2 and a metal sheath which surrounds the core. The core includes at least a first MgB.sub.2 core positioned on the center side, and a second MgB.sub.2 core positioned outside the first MgB.sub.2 core, and the density of the second MgB.sub.2 core is lower than the density of the first MgB.sub.2 core.

An MgB.sub.2-based superconducting wire for a liquid hydrogen fluid level sensor which can maintain an unimmersed portion of the MgB.sub.2-based superconducting wire for a liquid hydrogen fluid level sensor in a non-superconducting state even without heating the unimmersed portion is provided. A wire for a liquid hydrogen fluid level sensor comprises an MgB.sub.2-based superconductor which contains Mg, B, and Al. The critical temperature at which the electrical resistance becomes essentially zero is 20-25 K, and the transition width, which is the difference between the temperature at which the electrical resistance begins to decrease toward zero and the critical temperature, is at most 5 K.

An MgB.sub.2-based superconducting wire for a liquid hydrogen fluid level sensor which can maintain an unimmersed portion of the MgB.sub.2-based superconducting wire for a liquid hydrogen fluid level sensor in a non-superconducting state even without heating the unimmersed portion is provided. A wire for a liquid hydrogen fluid level sensor comprises an MgB.sub.2-based superconductor which contains Mg, B, and Al. The critical temperature at which the electrical resistance becomes essentially zero is 20-25 K, and the transition width, which is the difference between the temperature at which the electrical resistance begins to decrease toward zero and the critical temperature, is at most 5 K.

There is provided a method of manufacturing a continuous wire comprising forming a strip formed from at least one metallic material into a channel, placing at least one powder into the channel and sealing edges of the channel together to produce a wire, wherein the method further comprises mixing the powder with a carrier liquid to create a slurry and placing the slurry into the channel. The carrier liquid is chemically inert with respect to the at least one powder.

There is provided a method of manufacturing a continuous wire comprising forming a strip formed from at least one metallic material into a channel, placing at least one powder into the channel and sealing edges of the channel together to produce a wire, wherein the method further comprises mixing the powder with a carrier liquid to create a slurry and placing the slurry into the channel. The carrier liquid is chemically inert with respect to the at least one powder.

Systems and methods for performing optical annealing of an optical fiber disposed in a cryogenic environment subject to ionizing radiation, such as in a fusion energy source, are provided. The techniques include optically annealing the optical fiber using first light having a first peak wavelength and second light having a second peak wavelength different than the first peak wavelength. The first and second peak wavelengths may be selected to optically anneal defects associated with transient radiation-induced attenuation (RIA) and permanent RIA.

Systems and methods for performing optical annealing of an optical fiber disposed in a cryogenic environment subject to ionizing radiation, such as in a fusion energy source, are provided. The techniques include optically annealing the optical fiber using first light having a first peak wavelength and second light having a second peak wavelength different than the first peak wavelength. The first and second peak wavelengths may be selected to optically anneal defects associated with transient radiation-induced attenuation (RIA) and permanent RIA.

The present invention addresses a problem of providing an MgB2 wire material having a small reversible bending radius, a superconducting coil using the same, and an MRI without lowering a critical current value and a critical current density of the MgB2 wire material to an extreme. To solve the problem, provided are a superconducting wire having a plurality of MgB2 strands and a first base metal, a superconducting coil using the same, and an MRI, the superconducting wire being characterized in that in a cross section orthogonal to a wire longitudinal direction, a center point of an area surrounded by the plurality of MgB2 strands and a center axis of a cross section of the superconducting wire are disposed in separated positions.

The present invention addresses a problem of providing an MgB2 wire material having a small reversible bending radius, a superconducting coil using the same, and an MRI without lowering a critical current value and a critical current density of the MgB2 wire material to an extreme. To solve the problem, provided are a superconducting wire having a plurality of MgB2 strands and a first base metal, a superconducting coil using the same, and an MRI, the superconducting wire being characterized in that in a cross section orthogonal to a wire longitudinal direction, a center point of an area surrounded by the plurality of MgB2 strands and a center axis of a cross section of the superconducting wire are disposed in separated positions.