Superconductor and method of producing same

A superconductor comprising a crystalline matrix phase of a metal oxide expressed by the following formula (I):

• (R.sup.1.sub.1-x, Ba.sub.x)Ba.sub.2 Cu.sub.3 O.sub.d (I)
• wherein R.sup.1 stands for at least one trivalent element selected from the group consisting of La, Nd, Sm, Eu and Gd, x is a number greater than or equal to 0 and less than or equal to 0.5 and d is a number greater than or equal to 6.2 and less than or equal to 7.2, with Ba.sub.x substituting at the trivalent atom site of the crystal structure, and a multiplicity of regions dispersed in said matrix phase and each composed of a metal expressed by the following formula (II):
• (R.sup.2.sub.1-z, Ba.sub.z) (Ba.sub.1-y, R.sup.2.sub.y).sub.2 Cu.sub.3 O.sub.p (II)
• wherein R.sup.2 stands for at least one element selected from the group consisting of La, Nd, Sm, Eu and Gd, z is a number greater than or equal to 0 and less than or equal to 0.5, y is a number greater than 0 and less than or equal to 0.5 and p is a number greater than or equal to 6.2 and less than or equal to 7.2, with Ba.sub.z substituting at the trivalent atom site of the crystal structure and R.sup.2.sub.y substituting at the barium site of the crystal structure, said superconductor having a critical temperature of 92 K. or greater.

A superconductor comprising a crystalline matrix phase of a metal oxide expressed by the following formula (I):

• (R.sup.1.sub.1-x, Ba.sub.x)Ba.sub.2 Cu.sub.3 O.sub.d (I)
• wherein R.sup.1 stands for at least one trivalent element selected from the group consisting of La, Nd, Sm, Eu and Gd, x is a number greater than 0 and less than or equal to 0.5 and d is a number greater than or equal to 6.2 and less than or equal to 7.2, with Ba.sub.x substituting at the trivalent atom site of the crystal structure, and a multiplicity of regions dispersed in said matrix phase and each composed of at least one member selected from the group consisting of (a) a metal oxide expressed by the following formula (III):
• R.sup.3.sub.4-w Ba.sub.2+w Cu.sub.2 O.sub.10-q (III)
• wherein R.sup.3 stands for at least one element selected from the group consisting of La and Nd, w is a number greater than or equal to 0 and less than or equal to 0.2 and q is a number greater than or equal to 0 and less than or equal to 0.5 and (b) a metal oxide expressed by the following formula (IV):
• R.sup.4.sub.2 BaCuO.sub.5 (IV)
• wherein R.sup.4 stands for at least one element selected from the group consisting of Sm, Y, Eu, Gd, Dy, Ho, Er and Yb, the amount of said regions being not greater than 40% by weight based on the total weight of said matrix phase and said regions, said superconductor having a critical temperature of 92 K. or greater.

A superconductor comprising a crystalline matrix phase of a metal oxide expressed by the following formula (I):

• (R.sup.1.sub.1-x, Ba.sub.x)Ba.sub.2 Cu.sub.3 O.sub.d (I)
• wherein R.sup.1 stands for at least one trivalent element selected from the group consisting of La, Nd, Sm, Eu and Gd, x is a number greater than or equal to 0 and less than or equal to 0.5 and d is a number greater than or equal to 6.2 and less than or equal to 7.2, with Ba.sub.x substituting at the trivalent atom site of the crystal structure, a multiplicity of first regions dispersed in said matrix phase and each composed of a metal oxide expressed by the following formula (II):
• (R.sup.2.sub.1-z, Ba.sub.z) (Ba.sub.1-y, R.sup.2.sub.y).sub.2 CU.sub.3 O.sub.p (II)
• wherein R.sup.2 stands for at least one element selected from the group consisting of La, Nd, Sm, Eu and Gd, z is a number greater than or equal to 0 and less than or equal to 0.5, y is a number greater than 0 but less than or equal to 0.5 and p is a number greater than or equal to 6.2 and less than or equal to 7.2, with Ba.sub.z substituting at the trivalent atom site of the crystal structure and R.sup.2.sub.y substituting at the barium site of the crystal structure, and a multiplicity of second regions dispersed in said matrix phase and each composed of at least one member selected from the group consisting of (a) a metal oxide expressed by the following formula (III):
• R.sup.3.sub.4-w Ba.sub.2+w Cu.sub.2 O.sub.10-q (III)
• wherein R.sup.3 stands for at least one element selected from the group consisting of La and Nd, w is a number greater than or equal to 0 and less than or equal to 0.2 and q is a number less than or equal to 0 and greater than or equal to 0.5 and (b) a metal oxide expressed by the following formula (IV):
• R.sup.4.sub.2 BaCuO.sub.5 (IV)
• wherein R.sup.4 stands for at least one element selected from the group consisting of Sm, Y, Eu, Gd, Dy, Ho, Er and Yb, the amount of said second regions being not greater than 40% by weight based on the total weight of said matrix phase and said first and second regions, said superconductor having a critical temperature of 92 K. or greater.