An oxide superconductor includes: REBa.sub.2Cu.sub.3O.sub.7-x (RE being one element selected from a RE element group of Pr, Nd, Sm, Eu, Gd, Y, Tb, Dy, Ho, Er, Tm, Yb, and Lu). The RE includes at least three types of metallic elements (M1, M2, and M3), and the three types of metallic elements are any element of the RE element group selected in order. In an oxide system satisfying R(M1)20 mol % and R(M2)60 mol % and R(M3)20 mol %, R(M1) being an average metallic element ratio of M1 in M1+M2+M3, SD(Ms)>0.15 is satisfied at a position at 50% of an average film thickness of a cross section including the c-axis, Ms being the metallic element of not larger of R(M1) and R(M3), SD(Ms) being a standard deviation/average value of a concentration of Ms.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure including rare earth elements, barium (Ba), and copper (Cu). The rare earth elements include a first element which is praseodymium, at least one second element selected from the group consisting of neodymium, samarium, europium, and gadolinium, at least one third element selected from the group consisting of yttrium, terbium, dysprosium, and holmium, and at least one fourth element selected from the group consisting of erbium, thulium, ytterbium, and lutetium. When the number of atoms of the first element is N(PA), the number of atoms of the second element is N(SA), and the number of atoms of the fourth element is N(CA), 1.5(N(PA)+N(SA))N(CA) or 2(N(CA)N(PA))N(SA) is satisfied.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure containing rare earth elements, barium (Ba), and copper (Cu). The rare earth elements contain a first element which is praseodymium (Pr), at least one second element selected from the group consisting of neodymium (Nd), samarium (Sm), europium (Eu), and gadolinium (Gd), at least one third element selected from the group consisting of yttrium (Y), terbium (Tb), dysprosium (Dy), and holmium (Ho), and at least one fourth element selected from the group consisting of erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

The first object of the invention is directed to a method for modulating the number of charge carriers p in Cu.sub.xCr.sub.yO.sub.2, the method comprising the steps of (a) depositing a film of Cu.sub.xCr.sub.yO.sub.2 on a substrate; and (b) annealing at a temperature T the film of deposited Cu.sub.xCr.sub.yO.sub.2, wherein the subscripts x and y are positive numbers whose the sum is equal or inferior to 2. The method is remarkable in that the log (p)= T.sup.2+ T+, wherein the temperature T is expressed degree Celsius, wherein is a first parameter ranging from 0.00011 to 0.009, wherein is a second parameter ranging from +0.12 to +0.14, and wherein is a third parameter ranging from 27.40 to 22.42. The second object of the invention is directed to a semiconductor comprising Cu.sub.xCr.sub.yO.sub.2 deposited on a substrate and obtainable by the method in accordance with the first object of the invention.

The invention relates to a method for preparing a solid comprising a step of mixing a set of compounds comprising at least two Cu.sub.2(OH).sub.2CO.sub.3 powders of different particle sizes and at least one binder and the use of the solid prepared by means of this method.

The invention relates to a method for preparing a solid comprising a step of mixing a set of compounds comprising at least two Cu.sub.2(OH).sub.2CO.sub.3 powders of different particle sizes and at least one binder and the use of the solid prepared by means of this method.

The present invention provides an oxide superconducting bulk magnet which can obtain a sufficient amount of total magnetic flux, by preventing the superconducting bulk body from being broken due to electromagnetic stress and quenching phenomenon to enable magnetization by a strong magnetic field. An oxide superconducting bulk magnet comprising an oxide superconducting bulk body wherein RE.sub.2BaCuO.sub.5 is dispersed in a monocrystalline RE.sub.1Ba.sub.2Cu.sub.3O.sub.y; and an outer peripheral reinforcing ring fitted to the outer periphery of the oxide superconducting bulk body, wherein the outer peripheral reinforcing ring is made of a plurality of metal rings having a multiple ring structure in the radial direction, at least one of the plurality of metal rings has a thermal conductivity of 20 W/(m.Math.K) or more at a temperature of 20 to 70 K and at least one of the plurality of metal rings has a higher strength than the metal ring having a thermal conductivity of 20 W/(m.Math.K) or more.

Methods for producing oxide/metal composite components for use in high temperature systems, and components produced thereby. The methods use a fluid reactant and a porous preform that contains a solid oxide reactant. The fluid reactant contains yttrium as a displacing metal and the solid oxide reactant of the preform contains niobium oxide, of which niobium cations are displaceable species. The preform is infiltrated with the fluid reactant to react its yttrium with the niobium oxide of the solid oxide reactant and produce an yttria/niobium composite component, during which yttrium at least partially replaces the niobium cations of the solid oxide reactant to produce yttria and niobium metal, which together define a reaction product. The pore volume of the preform is at least partially filled by the reaction product, whose volume is greater than the volume lost by the solid oxide reactant as a result of reacting yttrium and niobium oxide.

An oxide superconductor includes: REBa.sub.2Cu.sub.3O.sub.7-x (RE being one element selected from a RE element group of Pr, Nd, Sm, Eu, Gd, Y, Tb, Dy, Ho, Er, Tm, Yb, and Lu). The RE includes at least three, types of metallic elements (M1, M2, and M3), and the three types of metallic elements are any element of the RE element group selected in order. In an oxide system satisfying R(1)20 mol % and R(M2)60 mol % and R(M3)20 mol %, R(M1) being an average metallic element ratio of M1 in M1+M2+M3, SD(Ms)>0.15 is satisfied at a position at 50% of an average film thickness of a cross section including the c-axis, Ms being the metallic element of not larger of R(M1) and R(M3), SD(Ms) being a standard deviation/average value of a concentration of Ms.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure including rare earth elements, barium (Ba), and copper (Cu). The rare earth elements include a first element which is praseodymium, at least one second element selected from the group consisting of neodymium, samarium, europium, and gadolinium, at least one third element selected from the group consisting of yttrium, terbium, dysprosium, and holmium, and at least one fourth element selected from the group consisting of erbium, thulium, ytterbium, and lutetium. When the number of atoms of the first element is N(PA), the number of atoms of the second element is N(SA), and the number of atoms of the fourth element is N(CA), 1.5(N(PA)+N(SA))N(CA) or 2(N(CA)N(PA))N(SA) is satisfied.