71 results about "Superconductor classification" patented technology

Methods and apparatuses for magnetic resonance imaging (MRI) and/or magnetic resonance spectroscopy comprising a superconducting main magnet operable to generate a uniform magnetic field in an examination region, at least one superconducting gradient field coil operable to apply a respective at least one magnetic field gradient within the examination region, and at least one RF coil that is operable to transmit and receive radio frequency signals to and from the examination region, and that is configured for cooling and comprises at least one of (i) a non-superconducting material that when cooled to a temperature below room temperature has a conductivity higher than that of copper at that temperature and (ii) a superconducting material. The main magnet, the gradient coils, and each of the at least one RF coil of a given system may each be implemented as high temperature superconductor materials.

A process for constructing a superconducting Josephson-based nonvolatile quantum memory device comprising: sequentially depositing on a silicon substrate a thermal oxide buffer layer, a superconductor bottom-electrode thin film, and an oxide isolation layer; patterning an active window having dimensions smaller that 10 nanometers in the oxide isolation layer; then sequentially depositing a bottom tunnel oxide layer, a charge-trapping layer, a top cap, and a top superconductor electrode layer; defining an active region by dry etching down to the oxide isolation layer while protecting the active region from etch chemistry; depositing a device passivation layer; defining and patterning vias from a top of the device passivation layer to the superconductor bottom-electrode thin film and to the top superconductor electrode of the active region; and depositing metal interconnect into the vias.

This invention concerns an improvement of the supercurrent carrying capabilities, i.e. the increase of critical current densities, of polycrystalline superconductor structures, especially of high-T_c superconductors fabricated with a coated conductor technique to provide superconducting layers containing flat grains. A superconductor with superior critical current density is obtained by joining, i.e. pressing or otherwise bringing into intensive facial contact, preferably superconducting contact, two or more such superconducting layers.

A new family of superconducting materials with critical temperature up to 55 K have recently been discovered, comprising a crystal structure with atomic layers of iron and arsenic alternating with atomic layers of rare-earth oxide or alkaline earth. The present invention identifies structures for integrated circuit elements (including Josephson junctions) in these and related materials. These superconducting circuit elements will operate at a higher temperature than low-temperature superconductors such as niobium, and may be easier to manufacture than prior-art high-temperature superconductors based on copper-oxides.

A superconductor coating inclusive, tape-like electrical conductor and windings using such conductor for magnets and electrical machines, etc. The described windings are suited for inclusion of successor superconductor materials such as yttrium barium copper oxide wherein magnetic flux related losses can potentially be excessive and preclude successful machine operation. Winding orientation and configuration of the conductor in an alternating current machine for lower losses are disclosed along with methods and apparatus for achieving the desired windings. Windings intended for differing locations within a machine of this type are made possible by the invention. Equations relating to magnetic losses incurred in such windings are also disclosed.

An NMR resonator for receiving RF signals at desired resonance frequencies from a measuring sample in a volume under investigation disposed about a coordinate origin (x,y,z=0), with a means for producing a homogeneous magnetic field B.sub.0 in the direction of a z axis, wherein superconducting conductor structures are disposed between z=-.vertline.z.sub.1.vertline. and z=+.vertline.z.sub.2.vertline. on a surface which is translation-invariant (=z-invariant) in the z direction at a radial separation from the measuring sample, is characterized in that a compensation arrangement is additionally provided on the z-invariant surface, which extends to values of at least +.vertline.z.sub.2.vertline.+0.5.vertline.r.vertline.>z> -.vertline.z.sub.1.vertline.-0.5.vertline.r.vertline., wherein .vertline.r.vertline. is the minimum separation between the measuring sample and the compensation arrangement, wherein the compensation arrangement comprises further superconducting conductor structures which are RF-decoupled from the RF resonator, with the conductor structures of the compensation arrangement and of the RF resonator being composed of individual surface sections ("Z-structures") which comprise superconducting structures and are disposed in the z-invariant surface to each extend along the entire length in the z direction of the conductor structures of the compensation arrangement and of the RF resonator, those superconducting structures being disposed such that decomposition of the surface of the Z structures into a plurality of small equally sized surface elements and application of a homogeneous test magnetic field along the surface normal of each surface element for all surface elements which differ only with respect to their z position, induces a magnetic dipole moment of the same strength. In this manner, the disturbing influence caused by magnetization of the superconductor is very well compensated for.

The essence of the invention is the use of supercooled superconductors for generation of high-frequency electric oscillations. The superconductor is supercooled, i.e. in the normal phase at a temperature lower than the critical transition temperature for superconductivity, under an applied electric energy source. In such non equilibrium conditions the superconductor can have negative differential conductivity which can be used as an active medium in generators of electric ( current and voltage) oscillations. Such generators can be used in the superconducing electronics. Oscillation can be modulated by the change of bias voltage, electrostatic doping by a gate electrode, or by light. When small amplitude oscillations are stabilized near to the critical temperature the generator can be used as a bolometer. The supercooled superconductors can be used also as transistors and frequency mixers. The negative differential conductivity of superconductor is created by the excess conductivity of fluctuation Cooper pairs. This behavior is predicted by the solution of the Boltzmann kinetic equation of the metastable in the normal phase Cooper pairs. Boltzmann equation for fluctuation Cooper pairs is derived as a state-of-the-art application of the microscopic theory of superconductivity.

The invention relates to a modularization reconfigurable method based on superconductive magnetic flux pinning connection and a simulation device applying the method. Particularly, interaction of an II-type high-temperature superconductor with a magnet and the characteristic of controllable magnetic field direction and size are utilized to establish reconfiguration of the modularization structure in a manner of establishing a superconductive magnetic flux pinning connecting interface. The magnetic flux pinning characteristic of the high-temperature superconductor in a superconducting state is fully utilized, the superconductive magnetic flux pinning connecting interface configured under the characteristic has certain rigidity and dampness and can be compared as connection by a spring having certain rigidity, and the superconductor can naturally enter the superconductive state in a space environment so that the reconfigurable method provides brand new developing idea for in-orbit assembly of a modularized spacecraft and has broad application prospect in the field of novel spacecraft development.

A system and method of controlling movement of magnetic material with at least first and second high temperature superconductors at spaced locations. A plurality of solenoids are associated with the superconductors to induce a persistent currents in preselected high temperature superconductors establishing a plurality of magnetic fields in response to pulsed currents introduced to one or more of the solenoids. Control mechanism in communication with said solenoids and/or said high temperature superconductors are used to demagnetize selected ones of the high temperature superconductors to reduce the magnetic fields substantially to zero. Magnetic material is moved between magnetic fields by establishing the presence thereof and thereafter reducing magnetic fields substantially to zero and establishing magnetic fields in other superconductors arranged in a predetermined configuration.

A solid-state quantum computing structure includes a dot of superconductive material, where the superconductor possesses a dominant order parameter with a non-zero angular momentum and a sub-dominant order parameter that can have any pairing symmetry. Alternately a solid-state quantum computing structure includes an anti-dot, which is a region in a superconductor where the order parameter is suppressed. In either embodiment of the invention, circulating persistent currents are generated via time-reversal symmetry breaking effects in the boundaries between superconducting and insulating materials. These effects cause the ground state for the supercurrent circulating near the qubit to be doubly degenerate, with two supercurrent ground states having distinct magnetic moments. These quantum states of the supercurrents store quantum information, which creates the basis of qubits for quantum computing. Writing to the qubits and universal single qubit operations may be performed via the application of magnetic fields. Read-out of the information may be performed using a SQUID microscope or a magnetic force microscope.

Some mechanical, electrical, and thermal properties of high Tc superconductors such as (Ba, Y) cuprates can be substantially improved by the dispersal of an appropriate metal in the superconductive body. For instance, mixing Ag particles with superconductive powder of nominal composition Ba2YCu3O7 and processing the mixture in the conventional manner can produce superconductive bodies having Tc of about 93 K and substantially greater fracture strength and normal state electrical and thermal conductivity than otherwise identical bodies that do not contain Ag particles.