We investigated the hardware implementation of an area-efficient superconducting lookup table (LUT) based on a single flux quantum (SFQ) logic by using a newly proposed small memory cell. The memory cell is composed of a nondestructive read-out (NDRO) flip-flop with input circuits that convert the input dc current to an SFQ pulse signal. The datum can be written to the selected memory cell in the 2-D

A method for modeling the superconducting state of an inhomogeneous film is proposed. The superconducting properties are changed by varying Ginzburg–Landau (GL) parameters over the film thickness. A system of 1-D equations was found using the standard minimization of the modified GL-free energy functional to describe the superconducting state of the inhomogeneous plate. Using the proposed method, the

In the framework of a design study for a post-LHC 100 TeV circular hadron collider, namely FCC-hh, high-gradient Nb 3 Sn lattice quadrupoles were investigated, following closely the specifications from the optic layout of that machine. After several iterations, a baseline design of the main quadrupole was selected and, then, included in the FCC-hh Conceptual Design Report. The article deals with the

High-temperature superconducting (HTS) cable has the merits of high capacity and small volume in the normal operation condition. However, the fault current, which could be 10–30 times of the nominal current, gives a great challenge to its thermal stability. Due to the overcurrent, the HTS tapes will quench to resistive state and result in generating large amount of heat, which may degrade or even damage

Superconducting 499.8-MHz radio frequency (rf) cavities have been proposed for the High Energy Photon Source (HEPS), a 6-GeV diffraction-limited synchrotron light source currently under construction in Beijing. Being an active third-harmonic system, two cavities shall provide 3.5-MV rf voltage and 400 kW of beam power to enable a complex rf gymnastics required by a novel injection scheme. Adopting

In the process of power compensation of the superconducting magnetic energy storage system (SMES) in the power grid, the existence of ac loss and eddy current loss will cause the magnet to heat up, and temperature rise is the main factor limiting the power output capability of SMES. This article proposes a state assessment method (SAM) that considers the temperature rise of the magnet. This method

Adiabatic quantum-flux-parametron (AQFP) logic is an energy-efficient superconductor logic family. In this article, we design binary counters, namely an up counter, a down counter, and an up/down counter, based on AQFP logic. These binary counters are T-flip-flop-based and count logic 1s in the input signal that is synchronized with excitation currents, which clock the counters. The internal state

Electrical machines with high-temperature superconducting (HTS) armature windings can benefit from high power density and efficiency. Furthermore, by using permanent magnets (PM) on the rotor, the cryogenic system can be significantly simplified compared with the fully superconducting (SC) machines or the machines with SC field windings. Compared with the conventional electrical machines, the performance

The second-generation high-temperature superconducting tapes (2G-HTS) such as the REBCO coated conductors are known for their strong mechanical properties and high current carrying capacity with low ac losses compared with first-generation HTS tapes as well as low-temperature superconductors. Therefore, they seem to be good candidates to assemble coils for superconducting rotating electric machines

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High temperature superconducting (HTS) coils have been designed for various applications such as magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR), and superconducting magnetic energy storage (SMES). Typically, the coils are in kilojoule range and have solenoid structure. These are mostly optimized with MATLAB and electromagnetic analysis using finite element method (FEM) software

This article evaluates the novel design approach of a 3 MW partially superconducting synchronous machine for electric aircraft propulsion. Its special feature is the application of an electromagnetic Halbach array for the field excitation to reduce the back yoke weight and thereby increase the overall output power density. The electromagnetic Halbach array is obtained by reproducing a permanent magnet

Reversible logic gates were previously implemented in superconducting circuits as adiabatic-reversible gates, which are powered with a sufficiently slow clock. In contrast, we are studying ballistic-reversible gates, where fluxons serve to both encode the information and power the gates. No power is applied to the gate apart from the energy of the input fluxons, and the two possible flux polarities

In this article, present the first detailed study of cascade switching in superconducting photon number resolving detectors. The detectors were made in the form of four parallel nanowires, coupled with the single-mode optical fiber and mounted into a closed-cycle refrigerator with a temperature of 2.1 K. We found out the value of additional false pulses ( N cas.sw. ) appearing due to cascade switching

Using a 2-D/3-D mixed electrothermal model, the quench behavior of an YBa 2 Cu 3 O 7-δ (YBCO) pancake magnet is investigated for operating temperature 30–65 K. From many simulations, it is found when the hot spot temperature T peak rises to the range [120 K, 300 K], both T peak and the normal zone length L NZ behave like exponential functions of the longitudinal normal zone propagation velocity (NZPV)

The A-V formulation based iterative algorithm method (IAM), developed at Paul Scherrer Institute, shows excellent performance in modeling the critical state magnetization-current in the ReBCO tape stacks after field-cooling magnetization. This article upgrades the function of the IAM, making it realistic to take into account the widely used E – J power law, as well as to model the magnetization-current

Fast detection of quench in high-temperature superconductors (HTS) is essential for the application of HTS magnets due to the low normal zone propagation velocity (NZPV). In this work, quench measurement of single-HTS wires has been carried out at 80 K through gas cooling. We use both electrical and thermoelectric methods to verify the ability of fiber Bragg grating (FBG) sensors to be applied to quench

This article presents a numerical model based on the definition of the scalar and vector potentials to calculate the ac losses generated in a high-temperature superconductor coated conductor tape by an ac transport current and by an ac external magnetic field applied with a generic orientation. The material characteristics of the different layers of a reference tape are included in the model equations

REBCO cable-in-conduit conductors at the level of tens of kiloamperes are being developed for application in fusion magnets. One important aspect to study is their performance in the case of a quench event. A conductor should survive from such an event without over design; therefore, they should be properly optimized. Using a simulation model developed based on THEA code, we studied the parameters

A 4.7 T compact superconducting magnet system for active shielding animal magnetic resonance imaging scanner was designed in this work. The resulting magnet consists of nine coaxial coils symmetrical about the z -axis. The innermost main coils and outermost shielding coils were made up of six inner coils with the positive current direction and three outer coils with the negative current direction,

The H-formulation, used abundantly for the simulation of high-temperature superconductors, has shown to be a very versatile and easily implementable way of modeling electromagnetic phenomena involving superconducting materials. However, the simulation of a full vector field in current-free domains unnecessarily adds degrees of freedom to the model, thereby increasing computation times. In this contribution

This article presents a semianalytical modeling approach for ac losses computation in high-temperature superconducting (HTS) stacks and coils near ferromagnetic parts. The Brandt's model is combined with the equivalent current model to take into account of the proximity of ferromagnetic materials with finite relative permeability. Large stacks of HTS tapes are considered. A homogenization is applied

We report on the response of a monolithic high $\mathrm{T_{c}}$ transition-edge bolometer to about 3 mmWave for the first time. The detector structure consisting of 400-nm $\mathrm{YBa_{2}Cu_{3}O_{7-x}}$ (YBCO) film on buffered yttria stabilized zirconia substrate without any coupled antenna, shows bolometric type responsivity to the 3-mmWave radiation at its transition temperature. The YBCO thin film

Magnetic field monitoring devices are essential for studying and operating high-temperature superconducting (HTS) magnets. Apart from conventional Hall sensor, passive optical fiber sensor is also an option for magnetic field monitoring. In this article, we proposed a novel access based on yttrium iron garnet magneto-optic (YM) sensor, which is one kind of optical fiber sensors, to measure magnetic

A compact superconducting magnet was constructed for low-energy nuclear physics experiments at the RAON heavy-ion accelerator facility. Conduction-cooled Helmholtz coils with a radius of 40 cm generate a uniform magnetic field of up to 1.51 T at a current of 71 A. The magnet has two crossing beam windows that allows the beam to pass either parallel (solenoid mode) or perpendicular (dipole mode) to

The short-circuit fault current on the dc side affects the operation safety of the multiterminal flexible HVdc (MTDC) transmission system seriously. The resistance-type superconducting fault current limiter (RSFCL) has received extensive attention in limiting the dc impact current because it has a fast response speed and zero impedance at a steady state. At present, there are so many works on the simulations

It is of great industrial interest and academic importance to investigate current harmonics impacts on AC losses of superconductors, especially in large-scale power devices. However, only effect of amplitude of in-phase current harmonics on AC loss has been studied in the works of literature. We numerically characterized nonsinusoidal AC loss of superconducting tape carrying harmonic currents with

This article presents a theoretical investigation of a resistive superconducting fault current limiter (R-SFCL) operating in a medium-voltage network. The considered power system presents a high level of fault current as well as a high transient recovery voltage. The simulation result shows that the R-SFCL not only limits the fault current to a desirable value, but also improves transient recovery

The second-generation high-temperature superconductor REBCO is one of the most valuable candidates that meet the requirements of future magnetic confinement fusion device. Quench behavior of an improved high-current REBCO composite conductor is simulated by a 1-D finite element method. Indium-tin alloy foil placed in the gap between stabilizer, jacket, and superconducting tape stacks can significantly

This article reports a study to identify optimal synthesis parameters for a pure boron precursor prepared following a patented process developed at CNR-SPIN laboratories, performed in the framework of a collaboration between CNR-SPIN and CERN. Boron is a precursor that plays a crucial role in the MgB 2 wire manufacturing, as a consequence, the synthesis parameters of the superconducting phase have

AC loss from Roebel cables with high-temperature superconducting strands are comparatively less, and they possess large current carrying capacity since they have a transposed structure. However, the strands should be strong enough to withstand various types of external loads during their operation. The present work simulates the performance of the Roebel strand against an external tensile load using

High-temperature superconducting (HTS) power equipment and tests at present require operating temperatures higher than the liquid nitrogen (LN 2 ). LN 2 is an important cryogenic refrigerant and liquid insulation material, which is widely used in HTS equipment. Although pressurized LN 2 can achieve temperatures higher than 77 K, it requires the use of sealed pressure vessels. Thus, a liquid cryogen

This article presents a superconducting material based planar broadband 3-way Wilkinson power divider which can be used in the Josephson quantum voltage device for the voltage standards. The 3-way Wilkinson power divider aims to improve the integration of Josephson voltage device compared to the commonly used 2-way power divider. A two-stage λ /4 section on each branch is used to increase the bandwidth

Railway transportation is of safety, convenience, economy, and environmental friendliness. However, with energy issues becoming increasingly important in this century, it is important to assess the situation in the transportation sector. When the superconducting cable is used as a feeder of the railway electrification system, the voltage drop can be significantly reduced. Therefore, the superconducting

Institute of Modern Physics is developing a Nb 3 Sn superconducting magnet system for a 45-GHz electron cyclotron resonance ion source. To achieve this complicated and challenging Nb 3 Sn magnet, a prototype with identical cross section but half the length of the magnet is proposed. A single sextupole coil prototype with 457 mm length has been fabricated and tested. This sextupole coil is 38 mm thick

The conceptual design of China fusion engineering test reactor (CFETR) is now ongoing. Its toroidal field magnets with a peak field of ∼15 T require a new conductor testing facility with higher background magnetic field to test and evaluate the performance of these conductors. As part of the study of CFETR, the facility named Super X (SUPERconducting eXperiment) is planning to be constructed at Institute

Various strand concept for high-temperature superconductor (HTS) flat tapes have been developed in the past few years for fusion magnet applications. We developed a round HTS strand with soldered multilayer copper tapes as filler and support called SaMiT following the technic path of twisted stacked-tape cable. DC tests performed under bending and twisting condition demonstrated that the proposed design

In recent years, the $H$ formulation of Maxwell's equations has become the de facto standard for simulating the time-dependent electromagnetic behavior of superconducting applications with commercial software. However, there are cases where other formulations are desirable, for example for modeling superconducting turns in electrical machines or situations where the superconductor is better described

A high-temperature superconducting (HTS) magnetic levitation (maglev), based on YBaCuO bulk superconductors and permanent magnet guideways, shows the potential to be applied in the future rail transportation. The maglev forces (levitation and guidance force) of the HTS maglev system, which bond the vehicle and the guideway, are the key factors of its dynamics studies. In practical operation, the HTS

We report demonstration of a readout circuit with high-throughput single flux quantum (SFQ) based encoders for a large-scale video imaging system with a conventional frame rate. The encoders are fully parallel and integrated on the same chip as linear arrays of serially connected superconductor stripline detectors (SSLDs), superconducting quantum interference device (SQUID) based comparators, and SFQ

Design and feasible verification of the round high-temperature superconducting (HTS) strand with REBCO tapes is the key technology for future fusion magnet application such as China Fusion Engineering Test Reactor (CFETR). Flat tape configuration of REBCO tapes and incompatibility with cable design based on round low-temperature superconducting (LTS) strand lead to the development of new cable technology

The short-circuit fault current on the dc side affects the operation safety of the multiterminal flexible HVdc transmission system seriously. The resistance-type superconducting fault current limiter (RSFCL) has received extensive attention in limiting the dc impact current because it has fast response speed and zero impedance at steady state. YBCO tapes are susceptible to delamination damage under

(RE)Ba 2 Cu 3 O 7-d (REBCO) coated conductors are becoming a preferred wire choice for many potential high temperature superconducting (HTS) applications, where additional metal layers are usually attached to the REBCO conductors to improve reliability and stability. In such cases, the eddy current loss in the metal layers is affected by the magnetic field shielding by adjacent REBCO coated conductors

In this article, the operating current and torque of surface-mounted permanent magnet (SPM) wind power generators with high-temperature superconducting (HTS) armature windings are analyzed. The influence of coil location and current angle on the electromagnetic performance is investigated systematically. The results show that the location of the HTS coils significantly affects the operating current

Superconducting electronics often require high-density microwave interconnects capable of transporting signals between temperature stages with minimal loss, cross talk, and heat conduction. We report the design and fabrication of superconducting 53 wt% Nb-47 wt% Ti (Nb47Ti) FLexible coAXial ribbon cables (FLAX). The ten traces each consist of a ${\oslash}$ 0.076 mm NbTi inner conductor insulated with

The local thermal disturbance will produce a joule heat. When the joule heat is larger than the minimum quench energy (MQE), it will lead to the phenomenon of a quench. The same problem exists in stacked superconducting tapes. In this article, the defects in REBCO tapes were created using the bending method. The voltage and temperature traces were measured during the quench process. The quench characteristics

Bifilar coil is one of the most applicable structures used for resistive-type superconducting fault current limiter. However, the turn-to-turn (longitudinal) insulation of the bifilar coil under lightning and switching impulse is rather different from the conventional pancake coil. The longitudinal insulation is characterized as the distributed circuit of the coil under high-frequency excitation, and

The Bi-2212 round wire has a multifilamentary structure, and the use of numerical method to study ac loss of such multifilamentary superconducting wire requires a long calculation time and large memory. Adopting a homogenization method at low frequency to study the ac loss of multifilamentary structural wire/tape has been proven to have high enough accuracy and can save a lot of calculation time. With

Due to the excellent electromagnetic properties of superconductor materials, superconducting generators have higher efficiency, lower weight and volume than traditional rotating machines. However, it is difficult to simulate the electromagnetic behavior in the superconducting generator due to the nonlinear $E - J$ relationship. A numerical model based on the $T - A$ formulation and moving mesh method

For high temperature superconducting (HTS) dc cables, one key issue is the necessity of using polymer dielectrics with higher dielectric strength at cryogenic temperature in liquid nitrogen. Nanocomposites have played an important role in improving the dielectric properties of epoxy resin (EP). This article investigates on the dc breakdown strength and the surface potential behavior of the epoxy/Al

In this article, a stochastic finite-difference time-domain (S-FDTD) method is proposed for analyzing the influence of physical size uncertainty on the time-domain response of superconducting transmission lines. The formulations of the proposed method are, in detail, derived with the two-fluid model and London equation. A typical superconducting microstrip line is simulated to verify the effectiveness

The enhanced racetrack model coil and racetrack model magnet constitute the current R&D Nb $_3$ Sn magnets under development at CERN aiming to achieve dipole fields of 16–18 T, the design baseline of the Future Circular Collider. This article reports the mechanical behavior of their common support structure, which underwent three different levels of room-temperature preload (with the bladders and key

Iron-free twin-aperture superconducting quadrupole in the interaction region is a key technology to increase the luminosity of high-energy future colliders, such as the circular electron-positron collider that China will build in the next ten years with a center-of-mass energy of 240 GeV and a small crossing angle of 33 mrad in the interaction region. The final focusing quadrupole QD0, which is 2.2

The quench protection in high-temperature superconducting (HTS) magnets is a well-known issue. Therefore, it is fundamental to have reliable models available for the analysis of the quench propagation in such magnets. The quench propagation in an ENEA HTS cable-in-conduit conductor, developed for fusion applications with the particular reference to an insert for the central solenoid of the Italian

Superconductive passive transmission lines (PTL) are widely used for signal routing in large-scale rapid single flux quantum (RSFQ) circuits. Due to the imperfect matching of the transmission lines between the driver and receiver, single flux quantum (SFQ) pulses are partially reflected. The round trip propagation time of these reflections can coincide with the following SFQ pulse, resulting in a decrease

Nonlinear conductive composite insulation has been widely used to reduce nonuniformities in the local high electric field of high-voltage direct-current equipment. The silicon carbide (SiC)/epoxy resin composites with nonlinear conductivities have great potential applications in high temperature superconducting equipment. In this article, SiC/epoxy resin composites with different filler loading are

Modern space-based telescopes operating in the terahertz (THz) spectral range require highly reflecting and cryogenically cooled optics ensuring extremely low noise. The idea of using high-temperature superconductor YBa 2 Cu 3 O 7-δ as a telescope's mirror coating for providing low dissipation and high reflectivity of the surface for the subTHz frequency band has been explored. We are presenting here

A 10 kA high-temperature superconductor current lead (HTS-CL) using a double-tube stainless steel (SS) shunt has been designed, fabricated, and tested at Institute of plasma physics, Chinese Academy of Sciences (ASIPP). The current lead consists of 80 parallel the second generation HTS coated conductor with critical current of 220 A at 77 K in self-field, a double-tube SS shunt, and Cu connectors.

The R&D of the central solenoid model coil (CSMC) is preparatory toward the final fabrication of the Chinese fusion engineering test reactor central solenoid coil. CSMC is being designed and partly fabricated in the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). During the process, new manufacturing technologies are developed and some design optimization is proposed. Based on the