246 results about "Superconducting thin films" patented technology

The invention provides nuclear magnetic resonance equipment realizing improved sensitivity of a probe for receiving a free induction decay (FID) signal in nuclear magnetic resonance (NMR) spectroscopy in a high frequency band of 600 MHz or higher. By manufacturing a solenoid coil of a higher filling factor by using a superconductor of extremely low resistance to high frequency current, sensitivity is increased. A superconducting thin film made of magnesium diboride (MgB₂) formed on a donut plate-type substrate is disposed so that the film surface becomes parallel with the uniform magnetic field. The object is realized by a probe made by a solenoid coil formed by connecting a plurality of coil parts by capacitive coupling via a normal metal lead.

The present invention provides a high-throughput system for the ex-situ formation of a superconducting thin film, such as rare-earth-barium-copper-oxide (REBCO), atop a continuous length of buffered metal substrate tape by heating a buffered metal substrate tape coated with precursors of REBCO These precursors, when heated and introduced to water vapor within a process chamber, decompose to form a functional superconducting thin film epitaxial to the buffer layer. A chamber such as a metalorganic chemical vapor deposition (MOCVD) reactor having showerhead and substrate heater assemblies designed for the creation of a long and wide deposition zone is well suited for use in the process the system. The chamber could be of cold-wall type where the walls are not heated or could of hot-wall type where the walls are heated.

The present invention relates to a method for producing a phase-separated layer useful as a flux pinning substrate for a superconducting film, wherein the method includes subjecting at least a first and a second target material to a sputtering deposition technique in order that a phase-separated layer is deposited epitaxially on a primary substrate containing an ordered surface layer. The invention is also directed to a method for producing a superconducting tape containing pinning defects therein by depositing a superconducting film on a phase-separated layer produced by the method described above.

The invention relates to a preparation method of a high-temperature superconducting thin film. The method specifically comprises steps as follows: providing an SrTiO3 substrate and placing the SrTiO3 substrate in a super-high vacuum system, growing an FeSe monocrystal layer on the surface of the SrTiO3 substrate by adopting a molecular beam epitaxy growing technology, and growing a protective layer with a layered crystal structure by adopting the molecular beam epitaxy growing technology and covering the surface of the FeSe monocrystal layer with the protective layer. By means of the method, the high-quality and ultrathin high-temperature superconducting thin film can be prepared, the starting temperature of superconducting transition of the thin film is above 54K, and the critical current density is higher than 106A/cm<2> when the starting temperature of superconducting transition of the thin film is 12K.

A mounting structure for a high temperature superconductor device, such as a filter, housed in a closed vacuum chamber and operated at a low temperature. The filter has dielectric substrate having: first and second surfaces; a circuit portion made of a superconducting thin film formed on the first surface of the dielectric substrate; and a ground layer consisting of a superconducting thin film formed on second surface of the dielectric substrate and a metal film deposited on the superconducting thin film. The mounting structure comprises: a device holder for holding the filter thereon; a conductive layer intervening between the ground layer of the filter and the device holder; urging parts for resiliently urging the filter toward the device holder. The conductive layer is made of a metal selected from among the group consisting of gold, silver, copper, aluminum and an alloy made of at least one of gold, silver, copper, and aluminum.The mounting structure can securely ground the ground layer of the filter enough to have an extremely low contact resistance as well as can have the amount of the released gas restricted.

The invention relates to a device and method for testing the superconductivity of a three-dimensional low-temperature superconducting thin film coil, belonging to the field of a low-temperature superconductivity technology and high-accuracy measurement. Particularly, the superconductivity test is carried out on the three-dimensional low-temperature superconducting thin film coil, the superconductivity of the three-dimensional low-temperature superconducting thin film coil is tested and researched by means of a vacuum and low-temperature environment provided by a low-temperature environmental system and a vacuum environmental system provided by the invention, and further the three-dimensional superconducting thin film coil is designed in an auxiliary manner. The invention designs a low-temperature system for testing the superconductivity of the three-dimensional low-temperature superconducting thin film coil, therefore, a low-temperature environment needs to be provided for superconducting coils, as described in the background technology, in the low-temperature environment provided by the invention, liquid helium is utilized as a refrigerant, and the working temperature of a testing system is ensure to reach 4.2K, namely minus 269 DEG C. Therefore, as the tested three-dimensional low-temperature superconducting thin film coil is a core part in payloads of an STEP (satellite test of the equivalence principle) jointly developed by the NASA (National Aeronautics and Space Administration) and the ESA (European Space Agency), the device and method provided by the invention belong to applied aerospace science and technology in terms of technology application.

The invention provides a method for preparing YBCO superconducting film target materials. The method comprises the following: A, a step of preparing YBCO superconducting-phase powder; B, a step of preforming, which is to put the powder prepared in a step A in a die, compress the powder by use of the pressure of between 20 and 30 MPa on a press so as to manufacture a sheet, put the sheet obtained through compression in a rubber sleeve, perform cold isostatic pressing under the pressure of between 150 and 200 MPa and obtain a superconducting sheet; C, a step of sintering the sheet, which is to sinter the superconducting sheet obtained in a step B in a box-type furnace for 20 to 30 hours at a sintering temperature of between 850 and 960 DEG C; and D, a step of performing oxygen permeation, which is to put the superconducting sheet sintered in a step C in a tubular furnace, perform oxygen permeation treatment for 2 to 3 hours at a temperature of between 450 and 500 DEG C and obtain the target material. The target material prepared by the method has the advantages of uniformity, good shape, high density and good superconducting performance. In addition, the method is low in cost and suitable for the mass production of the target material.

The invention provides a processing method for improving second generation high-temperature super-conducting strip interlayer binding force. The processing method comprises the following steps of taking a textured flexible strip as the base material, performing etching on an oxide layer on the surface of the strip, and controlling etching depth, width and patterns; and adopting the etched textured flexible strip to perform superconducting thin film deposition. Compared with the prior art, the processing method has the following beneficial effects: 1, the interlayer binding force of the second generation high-temperature super-conducting strip obtained by the preparation method is improved by more than one time, while the current-carrying capability attenuation is less than 20%; and 2, the second generation high-temperature super-conducting strip prepared by the preparation method has no influence to the structure and the preparation process of the subsequently prepared superconducting thin film.

The invention discloses a test method of crystal orientation matching relationship of nanometer zirconic acid lanthanum epitaxial layer and Ni-W substrate, belonging to the technical field of superconducting thin film performance tests. The test method is characterized in that secondary electronic amplification factor is adjusted and stepping distance is scanned in a system of thermal field emission scanning electron microscope SEM-electron backscattered diffractometer (EBSD), so that 5nA incidence election current can realize that the zirconic acid lanthanum epitaxial layer and Ni-W substrate texture are simultaneously displayed in one polar diagram under the condition that the lowest accelerating voltage is 6kV; one Kikuchi pattern comprises a zirconic acid lanthanum epitaxial layer and Ni-W substrate double phases; on the basis, commercial EBSD analysis software is adopted to measure the crystal orientation matching relationship of the zirconic acid lanthanum epitaxial layer and the Ni-W substrate in the growth directions of in-plane and epitaxial (c-axis). The method is visual and simple, does not need to perform surface pretreatment on the zirconic acid lanthanum and is suitable for other epitaxial material systems.

[Problem] To prepare a superconducting fault-current limiting element having a high sharing electric field at low cost.

[Means for Resolution] A superconducting fault-current limiting element including an insulator substrate; a superconductive thin film 3 formed on the insulator substrate; and an alloy layer 4 formed on the superconducting thin film 3, said alloy layer having a room-temperature resistivity higher by twice or more than the room-temperature resistivity of a pure metal, in which, when the superconducting thin film 3 goes into a normal conductive state by an overcurrent, the overcurrent flowing through the superconducting thin film 3 is transferred only to the alloy layer 4.

The invention discloses an yttrium barium copper oxide superconducting thin film mixed with samarium. Chemical composition of the superconducting thin film is YSmxBa2-xCu3Oy, wherein 0

The invention relates to a method for preparing nanometer lanthanum aluminate powders. The method comprises the following steps: mixing and stirring microemulsion with the composite of Span80 and Tween80 as the surfactant, with n-butanol as the assistant surfactant and respectively with water solution of lanthanum nitrate and aluminum nitrate and ammonia water as the aqueous phase; after separation, washing and drying, incinerating the product at 750-1000 DEG C to obtain globular lanthanum aluminate powders with high purity, light agglomeration and particle diameter range of 20-60mm. The method of the invention solves problems of the traditional nanometer lanthanum aluminate powder preparing method, including high temperature, large lanthanum aluminate powder size, morphological irregularity and serious agglomeration. The product can be used as key materials for microwave devices such as wave filters, harmonic oscillators, superconductive films, etc., and can also be applied as the catalyst for oxidative coupling of methane as well as hydrogenization and hydrogenolysis of hydrocarbons.

The invention discloses a device and method for testing the microwave surface resistance distribution of a high-temperature superconducting thin film. The testing device comprises a testing seat, a fixing assembly, a calibration assembly and a sealing cover, and the working resonant mode is TE012. The testing seat comprises a shielding shell, an input coupling structure, an output coupling structure, a supporting ring, a dielectric cylinder and a metal circular ring. The testing seat is loaded with the tested superconducting thin film to constitute a resonator. The fixing assembly is used for fixing the tested superconducting thin film, and the sealing cover is used for isolating the inside and the outside of the resonator. The device and method for testing the microwave surface resistance distribution of the high-temperature superconducting thin film have the advantages that the contradiction among the resolution ratio, the sensitivity and the universality of the testing device in the microwave surface resistance distribution test of the superconducting thin film is solved; the tested superconducting thin film can be effectively prevented from being pressed to be damaged; direct coupling can be effectively avoided, and high testing precision is achieved.

A superconducting article includes a substrate having a biaxially textured surface, and an epitaxial biaxially textured superconducting film supported by the substrate. The epitaxial superconducting film includes particles of Ba₂RENbO₆ and is characterized by a critical current density higher than 1 MA/cm² at 77K, self-field. In one embodiment the particles are assembled into columns. The particles and nanocolumns of Ba₂RENbO₆ defects enhance flux pinning which results in improved critical current densities of the superconducting films. Methods of making superconducting films with Ba₂RENbO₆ defects are also disclosed.

The invention discloses a method for manufacturing a magnesium diboride superconducting thin film micro-structure through annealing. According to the method, electron beams are used for annealing a magnesium diboride precursor film with micro-structure patterns in a vacuum. The magnesium diboride precursor film with the micro-structure patterns is an Mg/B multi-layer film manufactured with a film masking method. Elementary substances of magnesium and boron in the precursor film undergo a chemical reaction in annealing time of a second order of magnitude, and finally, the magnesium diboride superconducting thin film micro-structure with the conversion temperature higher than 35K is generated.

The invention relates to a konstantan alloy baseband used for a high-temperature superconducting coated conductor without magnetism and with high conductance and a method for preparing the same, belonging to the high conducting metal alloy material preparation process technical field. The compositions by weight percentage of the konstantan alloy baseband used for the high-temperature superconducting coated conductor are: 50 to 60 percent of Cu, 38 to 48 percent of Ni, and 1 to 5 percent of Mn. The alloy baseband can form a biaxially texture through each step in the technical process via annealing under a mixed atmosphere of Ar plus 4 percent Hz with an annealing temperature controlled to be between 700 and 1000 DEG C and the annealing time controlled for 30 to 90 minutes. The structure is advantageous to the coating of a YBCO superconducting thin film layer of the konstantan alloy baseband.

The invention relates to a method for preparing a magnesium diboride superconducting thin film by electron beam annealing. The method is characterized by annealing a magnesium diboride forerunner film in vacuum by adopting an electron beam, enabling a magnesium and boron simple substance in the forerunner film in the annealing time of the order of magnitude of seconds to perform chemical reaction, and generating the magnesium diboride superconducting thin film finally; and determining electron beam parameters and annealing time according to different thicknesses of the forerunner film and annealing temperatures in annealing, and finishing the annealing of thin films of different thicknesses through controlling energy and dosage of the electron beam accurately. The magnesium diboride superconducting thin film prepared by using the method in the invention has the advantages of stable performances, flat surface, higher transformation temperature than 35k, uniform annealing, and the method for preparing the film has high efficiency, and is simple in operation and the like, and can be used for the preparation of a plurality of functional thin films.

The invention provides a method for preparing high temperature superconducting thin film by chemical process. The method comprises the following steps: firstly preparing a precursor solution, by mixing Y(CH3COO)3, RE(CH3COO)3, Ba(CH3COO)2 and Cu(CH3COO)2 with ratio of (Y+RE) to Ba to Cu equaling to 1:2:3 (wherein RE is Nd, Sm, Eu, Gd and Dy) and dissolving in 20-30 mol percent aqueous trifluoroacetic acid solution; stirring to be uniform, performing vacuum drying by evaporation to the solvent to obtain gel; then adding methanol, stirring to be uniform, performing drying by evaporation to the solvent to obtain gel; then adding proper amount of methanol to prepare the precursor solution with the total concentration of metal ions of Y, RE, Ba and Cu being 0.8-3.0mol/L; then coating the precursor solution on a substrate; performing low temperature heat treatment at 400-410 DEG C to the coated thin film to decompose trifluoroacetic acid salt; and finally performing high temperature heat treatment at 800-850 DEG C and annealing process at 490-510 DEG C to form YBCO thin film doped with rare-earth element.

The invention provides a thin film deposition method and a Josephson junction preparation method. A method for depositing a thin film comprises that step of: 1) providing a substrate; 2) depositing afirst superconducting thin film layer have a first stress on that surface of the substrate under a first deposition condition; 3) depositeing a second superconducting thin film layer have a second stress on that surface of the first superconducting thin film layer under a second deposition condition, wherein the thickness and the material of the first superconducting thin film lay and the second superconducting thin film layer are the same, and the first stress is opposite to the direction of the second stress. The thin film is deposited by a step-by-step deposition method, the final preparedthin film meet the requirements in stress and roughness at the same time, and the performance and stability of the superconducting circuit device are improved. The Josephson junction prepared by the Josephson junction preparation method of the invention can effectively avoid the generation of leakage current and improve the performance of the Josephson junction.