Abstract: The films of this invention are high temperature superconducting (HTS) thin films specifically optimized for microwave and RF applications. In particular, this invention focuses on compositions with a significant deviation from the 1:2:3 stoichiometry in order to create the films optimized for microwave/RF applications. The RF/microwave HTS applications require the HTS thin films to have superior microwave properties, specifically low surface resistance, Rs, and highly linear surface reactance, Xs, i.e. high JIMD. As such, the invention is characterized in terms of its physical composition, surface morphology, superconducting properties, and performance characteristics of microwave circuits made from these films.

Abstract: The films of this invention are high temperature superconducting (HTS) thin films specifically optimized for microwave and RF applications. In particular, this invention focuses on compositions with a significant deviation from the 1:2:3 stoichiometry in order to create the films optimized for microwave/RF applications. The RF/microwave HTS applications require the HTS thin films to have superior microwave properties, specifically low surface resistance, Rs, and highly linear surface reactance, Xs, i.e. high JIMD. As such, the invention is characterized in terms of its physical composition, surface morphology, superconducting properties, and performance characteristics of microwave circuits made from these films.

Abstract: A new class of fundamental devices and methods for their manufacture and use. The bulk magnetic field replicators of the present invention require no precision machining or alignment to accurately reproduce magnetic fields of any complexity, nor extreme positional stability to maintain superconductivity. Such bulk devices may be formed of either low or high critical temperature superconductive materials, but are particularly adapted to formation from high critical temperature materials.

Abstract: There is provided RE-Ba-Cu-O oxide bulk superconductors in which considerably high critical current density is obtained at relatively high temperature. In the present RE-Ba-Cu-O bulk superconductors, RE is a combination of two or more elements selected from La, Nd, Sm, Eu and Gd, at least one of them being La, Nd and Sm and the remainder being Eu or Gd, in which a parent phase thereof comprises a RE.sub.1+x Ba.sub.2-x Cu.sub.3 O.sub.y crystal wherein -0.1<x<0.2 and 6.7<y<7.1, and 5 to 50% by volume of a RE.sub.2 Ba.sub.2 CuO.sub.5 fine dispersed phase having partide size of 0.01 to 0.5 .mu.m. Preferably, a total amount of Eu and Gd in the RE site is 40% by weight or less, while a slight amount of Pt may be added. As a result, the critical current density at liquid nitrogen temperature can be improved to 10,000 A/cm.sup.2 or more under a condition where a magnetic field of 3T is impressed parallel to c axis of the crystal.

Abstract: There are disclosed a high temperature superconductive material which can be plastically deformed, processed optionally into predetermined configurations and industrially mass produced and a method of manufacturing a formed body of the high temperature superconductive material. Mixed is a powder raw material which is mainly composed of: 10 to 50 mol % of at least one amide or nitride of alkali metal of Li, Na or K; 10 to 60 mol % of cyanide containing at least one metal selected from aluminum, copper, silver or gold; 5 to 50 mol % of at least one pure metal selected from aluminum, copper, silver or gold; and 10 mol % or less of at least one alkaline earth metal selected from Be, Mg, Ca, Sr or Ba. The powder raw material is pressed, and heated and sintered at the temperature of 673 K to 1553 K. In this manner, obtained is the plastically deformable high temperature superconductive material which can be optionally processed through forging, rolling and the like.

Abstract: Compounds of the of the general formula La.sub.3-z Me.sub.z Ba.sub.3 Ca.sub.1-v Nc.sub.v Cu.sub.7 O.sub.16+x, wherein Me can be a rare earth metal or an alkaline metal ion selected from the group consisting of yttrium (Y), ytterbium (Yb), sodium (Na) and Nc can be a 2+ion selected from the group consisting of magnesium (Mg) and cadmium (Cd) have been prepared as the HTSC in thin film superconductors. These compounds can be used as thin film high critical superconductors in thin film high critical temperature superconducting structures and antennas and in multilayered structures and devices such as Josephson junctions, broadband impedance transformers and both flux flow and field effect transistors.

Abstract: A high critical temperature and high critical current density superconductor is disclosed which contains 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 element selected from the group consisting of La, Nd, Sm, Eu and Gd, x is a number greater than 0 but not greater than 0.5 and d is a number between 6.2 and 7.2. Fine phases of RE211, RE422 and/or a metal oxide expressed by the formula (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 (R.sup.2 =La, Nd, Sm, Eu or Gd) may be dispersed in a matrix of the matrix phase of the formula (I). The above superconductor may be obtained by cooling a melt having a temperature of 1,000.degree.-1,300.degree. C. and containing R.sup.1, Ba, Cu and O at a cooling rate of 5.degree. C./hour or less under a partial pressure of oxygen of between 0.00001 and 0.05 atm, followed by annealing at 250.degree.-600.degree. C. in an oxygen atmosphere.

Abstract: An oxide superconductor composed of Cu, O and at least one of Ba, Sr and Ca and including alternately arranged at least one oxygen-deficient perovskite structure section and at least one infinite layer structure section, wherein the perovskite structure section consists of two first atomic layers and a second atomic layer sandwiched between the first layers, and wherein the infinite layer structure section consists of alternately arranged, third and fourth atomic layers. Each of the first layers consists of O and an element M.sup.1 selected from Ba, Sr and Ca and has an atomic ratio O/M.sup.1 of 1 or less, while the second layer consists of O and Cu and has an atomic ratio O/Cu of 2 or less. Each of the third layers consists of O and Cu and has an atomic ratio O/Cu of 2, while each of the fourth layers consists of an element M.sup.2 selected from Ba, Sr and Ca. A superconductor having a superconducting critical temperature of over 100 K. may be produced by heat treatment at 800.degree.-1,200.degree.C.

Abstract: Processes are provided for forming a superconductive composite, comprising a superconductive metal oxide and a ceramic. The composite may be formed in any desired shape. Liquid nitrogen can be held around the superconductor longer and delivered in a more controlled fashion and the composite has improved resistance to shatter and thermal shock. The ceramic also provides protection from atmospheric deterioration of the superconductive oxide.

Abstract: A superconductive material is in composition expressed as Y.sub.0.33 Ba.sub.0.67).sub.a Cu.sub.b (OF).sub.c. The usual a, b and c are so selected as to satisfy a relation expression ax (mix valence of A)+bx (mix valence of B)=cx (mix valence of C).

Abstract: Processes are provided for forming a superconductive composite, comprising a superconductive metal oxide and a ceramic. The composite may be formed in any desired shape. Liquid nitrogen can be held around the superconductor longer and delivered in a more controlled fashion and the composite has improved resistance to shatter and thermal shock. The ceramic also provides protection from atmospheric deterioration of the superconductive oxide.

Abstract: Provided is a metal oxide material represented by the composition formula of Ln.sub.a Sr.sub.b Cu.sub.3-x M.sub.x O.sub.c, where 2.7.ltoreq.a+b.ltoreq.3.3; 0.8 .ltoreq.a.ltoreq.1.2; 6.ltoreq.c.ltoreq.9; and 0.05 .ltoreq.x.ltoreq.0.7, Ln is at least one element selected from the group of elements of Y and lanthanoids or an atomic group consisting of said elements, and M is at least one element selected from the group of elements of Ti, V, Ga, Ge, Mo, W and Re or an atomic group consisting of said elements.

Abstract: A method of treating a part made of a superconductive ceramic of the (Ln).sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-.delta. type, where Ln is chosen from the rare earth elements other than cerium and terbium, the method being designed to reduce the value of .delta., in which method said part is heat treated in an oxidizing atmosphere, said method being wherein, during said treatment, an electric current with a density lying in the range 0.1 A/cm.sup.2 to 2 A/cm.sup.2 is caused to flow through said part, said treatment atmosphere having a partial pressure of oxygen lying in the range 0.1 atmospheres to 1 atmosphere, the treatment temperature lying in the range 200.degree. C. to 500.degree. C., and the duration of said treatment lying in the range 1 hour to 200 hours.

Abstract: Superconducting compositions characterized by the formula (Pb.sub.a A.sub.1-a)(Sr.sub.b Ba.sub.1-b).sub.2 (Ca.sub.c B.sub.1-c)Cu.sub.2 O.sub.7 wherein at least half the A atoms are Hg and the remainder, if any, are selected from one or more of Cd, Tl and Cu, B is selected from Y and the rare earths, a is from 0.3 to 0.7, b is from 0 to 1 and c is from 0.2 to 0.5 are disclosed. The superconductive compositions display zero-resistance temperatures up to about 80K.

Abstract: A high critical temperature and high critical current density superconductor is disclosed which contains 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 element selected from the group consisting of La, Nd, Sm, Eu and Gd, x is a number greater than 0 but not greater than 0.5 and d is a number between 6.2 and 7.2. Fine phases of RE211, RE422 and/or a metal oxide expressed by the formula (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 (R.sup.2 =La, Nd, Sm, Eu or Gd) may be dispersed in a matrix of the matrix phase of the formula (I). The above superconductor may be obtained by cooling a melt having a temperature of 1,000.degree.-1,300.degree. C. and containing R.sup.1, Ba, Cu and O at a cooling rate of 5.degree. C./hour or less under a partial pressure of oxygen of between 0.00001 and 0.05 atm, followed by annealing at 250.degree.-600.degree. C. in an oxygen atmosphere.

Abstract: In accordance this invention, there is provided a process for making a bulk superconductive material. In the first step of this process, a diffusion couple is formed from superconductor oxide and impurity oxide. Thereafter, the diffusion couple is heated to a temperature in excess of 800 degrees Centigrade, cooled at a controlled rate, and annealed.

Abstract: A novel metallic oxide of a Ln-Ca-Sr-Ba-Cu-B-O type and a process for manufacturing such a metallic oxide. The above metallic oxide has a composition expressed by the following formula (I):(Ln.sub.1-a Ca.sub.a)(Sr.sub.2-b Ba.sub.b)(Cu.sub.3-c B.sub.c)O.sub.d(I)wherein Ln is one or more kinds of elements selected from the group consisting of Y and lanthanoid elements except for Ce and Tb and wherein the following conditions are met: 0.1.ltoreq.a.ltoreq.0.5, 0.7.ltoreq.b.ltoreq.1.7, 0.1.ltoreq.c.ltoreq.0.5, and 6.5.ltoreq.d.ltoreq.7.5. A process for manufacturing the metallic oxide has the following steps. A mixture of materials including H.sub.3 BO.sub.3 used as a starting material of B is prepared. The resultant mixture is heated at a rate of 5.degree. C. or lower per minute up to 900.degree. C. or lower. Then, it is heated in an oxygen atmosphere at a range from 900.degree.-1050.degree. C.

Abstract: Provided is a metal oxide material represented by the composition formula of Ln.sub.a Sr.sub.b Cu.sub.3-x M.sub.x O.sub.c, where 2.7.ltoreq.a+b.ltoreq.3.3; 0.8.ltoreq.a.ltoreq.1.2; 6.ltoreq.c.ltoreq.9; and 0.05 .ltoreq.x.ltoreq.0.7, Ln is at least one element selected from the group of elements of Y and lanthanoids or an atomic group consisting of said elements, and M is at least one element selected from the group of elements of Ti, V, Ga, Ge, Mo, W and Re or an atomic group consisting of said elements.

Abstract: A superconductor material having a current density, J, of from about 30,000 to about 85,000 amps/cm.sup.2 at zero magnetic field and 77.degree. K is disclosed. The 123 superconductor, of the formula L.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. wherein L is preferably yttrium, is capable of entrapping sufficiently high magnetic fields and exhibits a low microwave surface resistance. The process of preparing the superconductor comprises compacting the bulk product, L.sub.1 Ba.sub.2 Cu.sub.3 O, and then sintering the reaction product at a temperature between about 40.degree. C. to about 90.degree. C. below its melting point, i.e., for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. at a temperature of approximately 940.degree. C. The composition is then heated in a preheated chamber maintained at approximately 1090.degree. C. to about 1,200.degree. C. (approximately 1,100.degree. C. for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta.

Abstract: The disclosed substance has a composition of a general chemical formula ofBi.sub.2 -(Sr.sub.2 Ca.sub.1).sub.1-x (La.sub.2 Y.sub.1).sub.x -Cu.sub.y -O.sub.z,where 0.4.ltoreq.x.ltoreq.1, y=2 and z=9-10.5, wherein said substance is an insulator or a semiconductor in the dark, and has a photoconductivity Q(.lambda.,T) in conjugate with superconductivity of a superconductor of an adjacent component of the Bi-SrCa-LaY-Cu-O system at and below a critical temperature (T) of less than 105-115K and below 65-85K at photoexcitation in an optical wavelength range (.lambda.) of 420-670 nm. The present invention relates to a method for producing the same and a superconductive optoelectronic device by using the same. The present invention also relates to an organized integration of the element or device into an apparatus to further develop a new field of "Superconductive Optoelectronics.

Abstract: A method of producing a microcrystalline RBa.sub.2 Cu.sub.3 O.sub.y structure where R denotes a lanthanide chosen from Y, La, Nd, Sm, Eu, Gd, Tb, Ho, Er, Tm, Yb and Lu and where y has a value between 6.9 and 7 starts with a powder of composition [x(123) ; (1-x) (7BaO--18CuO] where (123) denotes the 123 phase of RBaB.sub.2 Cu.sub.3 O.sub.y and where the value of x is between 0.01 and 1. The powder is compressed and sintered at a temperature below 920.degree. C. (the BaCuO.sub.2 and CuO binary eutectic temperature) to form a sample. The sample is placed on an oxide of the lanthanide R. The sample and its support undergo heat treatment enabling chemical reaction between the liquid part of the sample and its support whereby substantially all of the liquid part is consumed and highly regular 123 monocrystals are obtained. Cooling is applied. At least one annealing is carried out in pure oxygen at a temperature between 350.degree. C. and 500.degree. C. to obtain the orthorhombic form characteristic of RBa.sub.2 Cu.

Abstract: A new copper oxide superconductor of the formula Ln.sub.1-x M.sub.x Sr.sub.2 Cu.sub.3-y Ti.sub.y O.sub.7+.delta. is disclosed, and exhibits a Tc of 60.degree. K. with deviations from linear metallic behavior as high as 130.degree. K.

Abstract: A superconducting switch is composed of anisotropic magnetic material. The switch has a first superconducting section, a variable resistive section and a second superconducting section. An external magnetic field is applied so that the first and second superconducting sections remain superconducting and the resistive section changes resistance when the magnetic field applied exceeds the critical field of the variable resistance section. The different critical field regions are achieved by exploiting the natural critical field anisotropy of the ceramic superconductors (a previously unobserved phenomena in metal superconductors). By making the different sections with different orientations they will exhibit different critical field valves for a given direction of applied fields. The state of the switch is changed by either increasing or decreasing the external magnetic field about the critical field value of the resistive section of the switch.

Abstract: A high temperature superconducting material with the general formula GaSr.sub.2 Ln.sub.1-x MxCu.sub.2 O.sub.7.+-.w wherein Ln is selected from the group consisting of La, Ce, Pt, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Y and M is selected from the group consisting of Ca and Sr, 0.2.ltoreq.x.ltoreq.0.4 and w is a small fraction of one. A method of preparing this high temperature superconducting material is provided which includes heating and cooling a mixture to produce a crystalline material which is subsequently fired, ground and annealed at high pressure and temperature in oxygen to establish superconductivity.

Abstract: Provided is an oxide superconductor in which superconducting layer is sandwiched between two blocking layers having different compositions. Available superconducting layers include a one-layer system having one Cu-O.sub.2 sheet, a two-layer system having a mediating layer sandwiched between two Cu-O.sub.2 sheets, and a three-layer system having mediating layers sandwiched individually between three Cu-O.sub.2 sheets.Since the blocking layers are of different compositions, seventy-seven kinds of oxide superconductors can be obtained.

Abstract: The disclosed superconductive material has a characteristic in accordance with which electrical resistance disappears at a temperature of at least more than the boiling point of 20.3.degree. K. (-252.7.degree. C.) of liquid hydrogen and relates to La-Ba-Cu-O series superconductive material.Said superconductive material consists essentially of a composition having the formula(La.sub.1-x M.sub.x).sub.2 CuO.sub.4-x/2wherein, M=Ba or Ba(Sr, Ca) and x=0.04.about.0.20 as a main body, wherein the material has a K.sub.2 NiF.sub.4 crystal structure.

Abstract: A method of substantially aligning the superconducting grains of a multi-grained perovskite defect oxide type material, which material includes at least one superconducting phase. In the superconducting phase of such perovskite materials, the unit cells thereof include a plurality of substantially parallel metal oxide planes spacedly disposed along the c axis thereof. The aforementioned alignment of discrete grains of the multi-grained superconducting material occurs along the c axis.

Abstract: The present invention relates to an oxide superconductor comprising a composite oxide of RE , Ba and Cu, wherein the superconductor comprises a micro structure comprised of a monocrystalline REBa.sub.2 Cu.sub.3 O.sub.7-x phase (123 phase) and a RE.sub.2 BaCuO.sub.5 phase (211 phase) finely dispersed therein, the 123 phase being formed in a plurality of domains respectively for individual RE compositions and in the order of the 123 phase forming temperatures in respective layers.

Abstract: A non-linear superconducting junction device comprising a layer of high transient temperature superconducting material which is superconducting at an operating temperature, a layer of metal in contact with the layer of high temperature superconducting material and which remains non-superconducting at the operating temperature, and a metal material which is superconducting at the operating temperature and which forms distributed Sharvin point contacts with the metal layer.

Abstract: A superconductor material having a current density, J, of from about 30,000 to about 85,000 amps/cm.sup.2 at zero magnetic field and 77.degree. K. is disclosed. The 123 superconductor, of the formula L.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. wherein L is preferably yttrium, is capable of entrapping sufficiently high magnetic fields and exhibits a low microwave surface resistance. The process of preparing the superconductor comprises compacting the bulk product, L.sub.1 Ba.sub.2 Cu.sub.3 O, and then sintering the reaction product at a temperature between about 40.degree. C. to about 90.degree. C. below its melting point, i.e., for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. at a temperature of approximately 940.degree. C. The composition is then heated in a preheated chamber maintained at approximately 1090.degree. C. to about 1,200.degree. C. (approximately 1,100.degree. C. for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing barium. The process utilizes a temperature regime which overcomes problems associated with degradation of barium-containing multicomponent oxides caused by carbon dioxide.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing strontium, calcium or magnesium. The process utilizes a temperature regime which overcomes problems associated with degradation of strontium-, calcium- and magnesium-containing multicomponent oxides caused by carbon dioxide.

Abstract: An oxide superconductor which has a composition expressed by the following general formula and whose crystal structure is 1222-phase structure.Pb.sub.a (M.sub.1-x-y Ce.sub.x Sr.sub.y).sub.4 Cu.sub.3-a O.sub.z (I)(where M represents at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu, and a, x, y, and z denote the numbers which satisfy 0.3.ltoreq.a.ltoreq.0.7, 0<x.ltoreq.0.25, 0.3.ltoreq.y<0.5, 8.5.ltoreq.z.ltoreq.9.5, respectively). A Pb-based Cu oxide superconductor manufacturing method comprising the steps of mixing powders of raw materials containing at least Pb, Sr, Ce, M (where M represents at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu groups) and Cu in the proportion to have the composition shown in the general formula (I) above, optionally forming the mixed powder into a shape body, and firing the obtained powder mixture or the shape body in the temperature range of 900.degree.

Abstract: This invention relates to a process for restoring permeance of an oxygen-permeable ion transport membrane utilized to recover oxygen from an oxygen-containing gaseous mixture which contains water, carbon dioxide or volatile hydrocarbons. The process utilizes a class of ion transport membranes formed from multicomponent metallic oxides wherein permeance of such membranes had been believed to be permanently degraded by water and the like under conventional process operating temperatures. This invention provides a continuous process for restoring oxygen permeance of such membranes caused by deleterious interaction between the membrane and components such as carbon dioxide, water or hydrocarbons at elevated process temperatures.

Abstract: The present invention relates to novel multi-layer composite solid state membranes which are capable of separating oxygen from oxygen-containing gaseous mixtures at elevated temperatures. The membranes comprise a multicomponent metallic oxide porous layer having an average pore radius of less than about 10 micrometers and a multicomponent metallic oxide dense layer having no connected through porosity wherein the porous and dense layers are contiguous and such layers conduct electrons and oxygen ions at operating temperatures.

Abstract: A method of manufacturing a superconducting wire consisting essentially of mixing superconducting ceramic powders selected from a group selected from a group consisting of Y-Sr-Cu-O, Y-Ba-Cu-O, La-Sr-Cu-O, La-Ba-Cu-O and Bi-Sr-Ca-Cu-O with metal powder, filling the mixture in a metal pipe and forming the mixture into wire by at least one of extrusion, drawing and swaging. The resulting wire would have superconductivity which is not reduced upon distortion by external stress.

Abstract: A process of forming on a substrate a coating of a precursor of a crystalline rear earth alkaline earth copper oxide or heavy pnictide mixed alkaline earth copper oxide electrical conductor and converting the precursor to the crystalline electrical conductor.

Abstract: Oxide materials of (L.sub.x A.sub.1-x).sub.i MO.sub.y, (L.sub.x A.sub.1-x).sub.i M.sub.1-z Cu.sub.z O.sub.y and (L.sub.x A.sub.1-x).sub.i MO.sub.j-.delta. G.sub.k, wherein L is Sc, Y, lanthanides, etc.; A is Ba, Sr. Ca, etc.; M is V, Nb, Ta, T, Zr or Hf; 0<x<1; 0<z<1; i=1, 3/2 or 2; 0<y.ltoreq.4; Gis F, Cl or N; .delta. is oxygen defect, and having a perovskite-like crystal structure, show superconductivity at a temperature higher than the liquid nitrogen temperature.

Abstract: A superconductive material is disclosed which has the following composition:(R.sub.1-x Ca.sub.x)(Ba.sub.1-y La.sub.y).sub.2 Cu.sub.4 O.sub.8wherein R is at least one element selected from Y, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu, x is a number in the range of 0-0.3 and y is a number in the range of 0.001-0.3 with the proviso that y is not greater than 0.2 when x is not 0.

Abstract: In a ceramic superconducting composition, Ag20 is added thereto in an amount of 0.1 wt. % to 70 wt. % per mole of LaBa2Cu3O3-.delta.. The critical current density of the ceramic superconducting composition is affected by heat treatment conditions. The critical electric current density of the ceramic superconducting composition is increased when it is prepared through heat treatment while controlling the partial pressure of oxygen in a heat treatment atmosphere in steps with successive stages including a temperature-elevating step, a sintering step, a temperature-lowering step, and an annealing step.

Abstract: Finely divided, homogeneous and easily sintered superconducting powders of at least one rare earth element, e.g., yttrium and/or lanthanum, at least one alkaline earth metal, e.g., barium, calcium and/or strontium, and at least one transition metal, e.g., copper, nickel, manganese, cobalt and/or iron, and oxygen, are produced by (a) solubilizing, in water, the nitrates and/or acetates of at least one rare earth element, at least one alkaline earth metal, and at least one transition metal; (b) atomizing such solution to dryness; (c) calcining the dried product; and, optionally; (d) grinding the calcined material.

Abstract: Disclosed is a method of manufacturing an oxide superconductor containing at least an alkaline earth metal and copper. This method comprises the steps of heating a material substance containing elements constituting the oxide superconductor, in an atmosphere having an oxygen partial pressure of at most 50 Torr at a temperature ranging from 500.degree. C. to 1000.degree. C., and then heating the material substance in an oxygen-containing atmosphere. Also disclosed herein is a method of manufacturing composite oxide powder which is the precursor of the oxide superconductor. This method comprises the steps of heating the material substance in an atmosphere having an oxygen partial pressure of at most 50 Torr at a temperature ranging from 500.degree. C. to 1000.degree. C., and crushing the material substance into powder.

Abstract: High current density tunnel junction devices (12) are fabricated by ion implantation of ions (26) to form buried semiconducting layers (24) in originally homogeneous high temperature superconducting oxide layers (18) formed on superconducting oxide substrates (14). Contacts (20, 22) are made to the oxide substrate and to the oxide layer. In an alternative embodiment, the junction devices (12') are fabricated by ion implantation of ions in portions of the substrate. In this embodiment, contacts are made to the oxide substrate and to portions of the substrate overlying the buried semiconducting junctions.

Abstract: Orthorhombic perovskitic metal-oxide superconductors of the lanthanum-barium-copper type (LaBa.sub.2 Cu.sub.3 O.sub.y) wherein Y ranges from 6.8 to 7.0, and T(R=0) is at least about 90.degree. K., can be prepared by sintering and annealing a substantially stoichiometric calcined mixture of one or more sources lanthanum, barium and copper under conditions wherein the time and temperature of exposure to oxygen during the sintering and annealing operations is controlled.

Abstract: A process for preparing the superconductive material MBa.sub.2 Cu.sub.3 O.sub.x, M being, inter alia, yttrium and x being from about 6.5-7 and a precursor material MBa.sub.2 Cu.sub.3 O.sub.y, y being from about 6-6.5, by controlled heating and cooling in a controlled atmosphere.

Abstract: A method for producing uniform mixed metal oxides, such as superconducting mixtures including Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, in which such metals are precipitated as their oxalates from alcoholic solutions of the metals as the salts of a carboxylic acid.

Abstract: The invention relates to the preparation of high purity, chloride- and alkali metal-free copper (II) alkoxides by means of the reaction of an alcoholic alkali metal alkoxide solution with copper (II) fluoride; ammoniating the resulting solution to render soluble the resulting copper (II) alkoxide; and filtering the resulting solution to obtain an alkali metal- and chloride-free alcoholic copper (II) alkoxide solution. The resulting solution is useful in the preparation of superconducting compound such as yttrium-barium-copper oxide superconductor.