Abstract: Embodiments of the present invention reconstruct a waveform at a receiver-end of a channel from an observed waveform physically measured at a probe point near the middle of the channel, where the channel is corrupted by reflections. The channel may be a memory channel of a high-speed I/O interface, for example. Equations to derive the waveform may be created using linear network analysis and/or signal processing, for example. S-parameters may be derived from simulated models representing components from the probe point to the load. The s-parameters together with the load impedance are used to recreate the desired waveform free from corruption due to reflections.

Abstract: A dissipative device has a planar configuration with one or more resistor elements formed on an insulating substrate. Conductors are formed on the insulating substrate and are coupled to the resistor element(s) to transmit signals to/from the resistor element(s). The geometry of and materials for the dissipative device allow the conductors to act as heat sinks, which conduct heat generated in the resistor element(s) to the substrate (and on to a coupled housing) and cool hot electrons generated by the resistor element(s) via electron-phonon coupling. The dissipative device can be used in cooling a signal to a qubit, a cavity system of a quantum superconducting qubit, or any other cryogenic device sensitive to thermal noise.

Abstract: A refrigerant liquid level measuring device that measures a refrigerant liquid level in a short period is provided. A series sensor arrangement includes a plurality of sensor elements electrically connected in series. The sensor elements each have a superconducting wire and a normal conductor heater electrically connected to the wire, and the superconducting wire and the normal conductor heater are in thermal contact with each other. The series sensor arrangement is provided to cross the liquid level of refrigerant liquid in a container that stores the refrigerant liquid and one of the sensor elements and the other sensor elements in the series sensor arrangement are positioned on one another in the vertical direction. The series sensor arrangement is supplied with electric current, so that the liquid level of the refrigerant is measured by measuring the electrical resistance value of the normal conductive part of the super conducting wires in the series sensor arrangement.

Abstract: A method and system for balancing a rotary member. The system preferably comprises balancer stand, a stator element including and a levitation element. The rotary member is coupled with the levitation element. The rotary member and the levitation element are positioned above the stator element which preferably comprises a superconductor element. The rotary member and levitation element are suspended above the stator element when the superconductor element is activated through field cooling. The rotary member is titled with respect to a direction of gravity such that an imbalanced portion of the rotary member rests at the lowest point of the rotary member. The imbalanced portion is thereby identified and can be corrected.

Abstract: A cryogenic apparatus for microscopy of physical properties of an object including a thin, stiff, transparent substrate or window within the outer wall of the vacuum space of a dewar and a cryogenic sensor within the vacuum space and spaced very close distances to the window. This construction allows for positioning a sample for measurement outside of the vacuum space, at room temperature or higher and for microscopy of physical properties of the sample by monitoring the output from the cryogenic sensor as it is scanned along the surface of the sample.

Abstract: The order parameter of a superconductor is reduced by injecting spin-polarized carriers into the superconductor. The reduction in the order parameter is used to modulate the critical current of the superconductor. In a typical embodiment, a current is caused to flow through a superconductor. Spin polarized electrons are then injected into the path of the current in the superconductor by biasing a magnetic metal with respect to a terminal of the superconductor. The bias current may be varied to modulate the injection and thus the flow of current through the superconductor.

Abstract: A method of measuring a cryogenic fluid level utilizing a high temperature ceramic superconductor material driven above its level of critical current density. A high temperature ceramic superconductor is placed in cryogenic fluid and a voltage is applied between two points on the superconductor. The voltage drop is then measured at a third point on the superconductor. This voltage drop corresponds to the change in cryogenic fluid level, and thus can be used to measure the fluid level. Sensitivity of the measurement is increased by driving the high temperature ceramic superconductor above its level of critical current density.

Abstract: Method and arrangement for detecting the level of a liquid cryogen having a predetermined boiling point and which is being held in a container relative to the bottom of the container. The arrangement includes a container which receives the liquid cryogen and a longitudinal extending sensing member having a length extending from the bottom of the container to a level that is greater than any depth experienced for the liquid cryogen. The sensing member is vertically disposed in the container with one end in contact with the bottom of the container and the other end extending out of the liquid cryogen. The sensing member is composed of a high temperature superconductor material having a critical temperature that is higher than the predetermined boiling point of a selected cryogen. An electrical current is passed through the sensing member and the voltage drop across the sensing member is measured.

Abstract: A non-destructive testing equipment comprises a magnetic field generator for generating a uniform magnetic field, and a magnetic sensor accommodated in a thermal insulation container and filled with a liquid nitrogen. The thermal insulation container is located within a magnetic shield container having an opening. The magnetic sensor includes a SQUID that is a magnetic sensor having very high sensitivity. The magnetic sensor can detect, through the opening, an appreciable variation of the magnetic field that is caused by small impurities or minor defects contained in the object to be tested.

Abstract: An apparatus and method for continuously monitoring the liquid nitrogen level a liquid nitrogen container and automatically refilling liquid nitrogen from a liquid nitrogen reservoir when the liquid nitrogen in the container falls below a predetermined level. The apparatus comprises a liquid nitrogen level sensing element, which contains a superconducting material, such as a YbaCuO type superconductiing material, disposed on a non-conducting substrate, such as magnesium oxide. The superconducting material is selected such that it has a critical temperature approximately equal to the boiling point temperature of liquid nitrogen. The superconducting material is placed near the predetermined level and, under normal conditions, the superconducting material exhibits zero or near zero resistance.

Abstract: The surface characteristics with respect to a high-frequency electromagnetic field of a material to be tested are measured by placing opposite a flat mirror material to be tested one of a pair of concave spherical reflection mirrors fabricated in the same way and formed with high-reflectance circular coupling regions, placing the other spherical reflection mirror at a position symmetrical to the one reflection mirror with respect to the flat mirror material as the plane of symmetry, measuring the Q value of the open resonator formed by the one reflection mirror and the flat mirror material, removing the flat mirror material from the optical axis, measuring the Q value of the open resonator formed by the pair of spherical reflection mirrors, calculating the absolute value of the reflectance of the flat mirror material to be tested from the difference between the two measured Q values, and calculating the phase of the reflected wave at the surface of the flat mirror material to be tested from the measured reson

Abstract: Apparatus and method for non-contact temperature measurement of a film growing on a substrate which accounts for the change in emissivity due to the change in film thickness. The system employs an adaptively calibrated pyrometer wherein the substrate emittance is continuously computed so that the temperature measurement is accurate regardless of the emittance variation. The new system is easily constructed by adding data processing system software and hardware to conventional pyrometers.

Abstract: An instrument for non destructive evaluation (NDE) is called an electromagnetic microscope, formed by superconductive microprobes arrayed in parallel rows. When moved over a test piece, the array generates a scanned image of flaws, stress variations or changes in composition. Each microprobe has a drive coil a few mm in radius that encircles pickup loops forming a concentric, coplanar gradiometer 1 mm or less in diameter, coupled to a superconducting quantum interference device (SQUID). Drive coils transmit an oscillating magnetic field that induces eddy or magnetization currents in conductive or ferromagnetic materials, respectively. The gradiometer senses distortions in paths of induced currents. The sensitivity of SQUIDs increases sensitivity, penetration depth, and spatial resolution of flaws.

Abstract: A converse transformation matrix generation approach is used either i) to late a lattice structure of one crystalline material to the lattice structure(s) of one or more other crystalline materials for determining interlattice relationships which allow materials to be identified and classified relative to other materials; or ii) to relate a lattice structure of a material to itself for determining lattice symmetry. In particular, matrices which transform any primitive cell defining a lattice structure either into itself or into another cell defining a second lattice structure to within predetermined maximum tolerances of the cell parameters are generated.

Abstract: An apparatus for observing a superconductive phenomenon is disclosed. In the apparatus, a cooling unit cools a superconductor having a threshold temperature at which the superconductor changes from the normal conductive phase to the superconductive phase, and a magnetic field is applied thereto. A current is supplied to the superconductor, and there are clearly observed a phenomenon on which an electric resistance thereof becomes zero at a threshold temperature thereof, a phenomenon on which the superconductor changes from the normal conductive phase to the superconductive phase at a threshold current to be supplied thereto, and a phenomenon on which the super conductor changes from the normal conductive phase to the superconductive phase at a threshold magnetic field to be applied thereto.

Abstract: A cryogenic level sensor assembly. A sensor assembly includes a continuous length of high temperature ceramic superconductor material, an exterior housing for holding the length of ceramic superconductor material, a support material disposed between the ceramic superconductor material and the exterior housing, and a resilient retention material disposed opposite the ceramic superconductor material for holding the superconductor material while allowing expansion and contraction thereof during thermal cycling.

Abstract: Characteristics of a superconductor such as a repulsive displacement of a superconductor against a magnet or a rotational resistance of the superconductor due to flux-pinning in the superconductor are measured by supporting the superconductor in a non-contact mode; disposing a magnet at a position opposite to the superconductor; and moving the superconductor toward the magnet relatively or increasing the magnetic force of the magnet. The measurement may be carried out while the superconductor is applied with a load or is rotating.

Abstract: A method of evaluating the characteristics of superconductors, comprising: irradiating light to a superconductor held at a predetermined temperature; detecting light transmitted through the superconductor and composing a spectrum of the transmitted light; and using the obtained spectrum, calculating a ratio of the number of electrons contributing to a normal conduction to the number of electrons contributing to a superconduction in the superconductor, the ratio being effective at said predetermined temperature. A process and an apparatus for forming superconductor films by using the method are also disclosed.

Abstract: In a strain measuring device employing a magnetic permeability detector means to detect an amount of strain in a passive member as changes of magnetic permeability in a magnetostrictive layer, a magnetic shielding layer is formed on the surface of the passive member, and the magnetostrictive layer is formed thereon so as to lessen the adverse effects of the passive member caused by the magnetic characteristics of the passive member in strain measurement, that is, to reduce measurement errors. Alternatively, a magnetostrictive layer is formed on the surface of the passive member, or a magnetic shielding layer is partially formed on the surface of the passive member of a soft magnetic material with high permeability, so as to lessen the influence of the passive member caused by thermal stresses of the passive member in strain measurement, that is, to reduce measurement errors. Further, there is provided a strain measuring device which facilitates formation of the magnetostrictive layer.

Abstract: A highly sensitive force detector using a tunneling junction as a strain gauge is disclosed. The tunneling junction is connected to a deflection member which receives the force to be measured. The junction is connected in a nulling circuit to a magnetic flux motor which generates a restoring force precisely equal to the force to be measured. The magnetic flux required by the flux motor to do so is measured by a SQUID, the output of which is directly proportional to the flux to be measured. The device has applications in pressure sensing, weighing, gravity measurements, detection of massive objects, and elsewhere.

Abstract: A cryogenic gyroscope for detecting the angular velocity of a rigid system without reference to an external inertial system comprises a closed rigid casing made of a sueprconducting material and kept below its critical superconducting temperature, for example, by immersion in a bath of liquid helium. A rotation-detector device is situated within the superconductor casing. This device, which is rigidly supported by the wall of the casing, includes at least one component of ferromagnetic material, constituted by a plurality of ferromagnetic strips intercalated with layers of electrically-insulating material.

Abstract: In a strain measuring device employing a magnetic permeability detector means to detect an amount of strain in a passive member as changes of magnetic permeability in a magnetostrictive layer, a magnetic shielding layer is formed on the surface of the passive member, and the magnetostrictive layer is formed thereon so as to lessen the adverse effects of the passive member caused by the magnetic characteristics of the passive member in strain measurement, that is, to reduce measurement errors. Alternatively, a magnetostrictive layer is formed on the surface of the passive member, or a magnetic shielding layer is partially forrmed on the surface of the passive member of soft magnetic material with high permeability, so as to lessen the influence of the passive member caused by thermal stresses of the passive member in strain measurement, that is, to reduce measurement errors. Further, there is provided a strain measuring device which facilitates formation of the magnetostrictive layer.

Abstract: The invention relates to a novel apparatus for detecting as well as quantifying superconductivity characterized by a rigid-stemmed pendulum used to support the superconductive sample for free-swinging movement about a low-friction fulcrum in a magnetic field effective to swing the pendulum to one side, connecting both a first mechanism to the pendulum operative to sense the movement of the pendulum and generate a signal proportional thereto along with a second mechanism effective to receive such a signal from the first mechanism and react thereto in a manner to null the movement of the pendulum along with the sample suspended therefrom, and, finally, connecting a signal processing mechanism into the system whereby the signal generated by the first mechanism is quantified as a measure of the superconductive properties of the sample.