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1

Nano-fabricated superconducting radio-frequency composites, method for producing nano-fabricated superconducting rf composites  

DOE Patents [OSTI]

Superconducting rf is limited by a wide range of failure mechanisms inherent in the typical manufacture methods. This invention provides a method for fabricating superconducting rf structures comprising coating the structures with single atomic-layer thick films of alternating chemical composition. Also provided is a cavity defining the invented laminate structure.

Norem, James H.; Pellin, Michael J.

2013-06-11T23:59:59.000Z

2

Superconducting RF Cryomodule Demagnetization  

E-Print Network [OSTI]

This note presents measurements that support the proposition that it is feasible to demagnetize a fully assembled superconducting RF cryomodule.

Crawford, Anthony C

2015-01-01T23:59:59.000Z

3

A new microphonics measurement method for superconducting RF...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

new microphonics measurement method for superconducting RF cavities Re-direct Destination: Mechanical vibrations of the superconducting cavity, also known as microphonics, cause...

4

SUPERCONDUCTING RF-DIPOLE DEFLECTING AND CRABBING CAVITIES  

SciTech Connect (OSTI)

Recent interests in designing compact deflecting and crabbing structures for future accelerators and colliders have initiated the development of novel rf structures. The superconducting rf-dipole cavity is one of the first compact designs with attractive properties such as higher gradients, higher shunt impedance, the absence of lower order modes and widely separated higher order modes. Two rf-dipole designs of 400 MHz and 499 MHz have been designed, fabricated and tested as proof-of-principle designs of compact deflecting and crabbing cavities for the LHC high luminosity upgrade and Jefferson Lab 12 GeV upgrade. The first rf tests have been performed on the rf-dipole geometries at 4.2 K and 2.0 K in a vertical test assembly with excellent results. The cavities have achieved high gradients with high intrinsic quality factors, and multipacting levels were easily processed.

Delayen, Jean [ODU, JLAB; De Silva, Paygalage Subashini [ODU, JLAB

2013-09-01T23:59:59.000Z

5

Investigation of Microscopic Materials Limitations of Superconducting RF Cavities  

SciTech Connect (OSTI)

The high-field performance of SRF cavities is often limited by breakdown events below the intrinsic limiting surface fields of Nb, and there is abundant evidence that these breakdown events are localized in space inside the cavity. Also, there is a lack of detailed understanding of the causal links between surface treatments and ultimate RF performance at low temperatures. An understanding of these links would provide a clear roadmap for improvement of SRF cavity performance, and establish a cause-and-effect ‘RF materials science’ of Nb. We propose two specific microscopic approaches to addressing these issues. First is a spatially-resolved local microwave-microscope probe that operates at SRF frequencies and temperatures to discover the microscopic origins of breakdown, and produce quantitative measurements of RF critical fields of coatings and films. Second, RF Laser Scanning Microscopy (LSM) has allowed visualization of RF current flow and sources of nonlinear RF response in superconducting devices with micro-meter spatial resolution. The LSM will be used in conjunction with surface preparation and characterization techniques to create definitive links between physical and chemical processing steps and ultimate cryogenic microwave performance. We propose to develop RF laser scanning microscopy of small-sample Nb pieces to establish surface-processing / RF performance relations through measurement of RF current distributions on micron-length scales and low temperatures.

Anlage, Steven [University of Maryland

2014-07-23T23:59:59.000Z

6

Superfluid helium cryogenic systems for superconducting RF cavities at KEK  

SciTech Connect (OSTI)

Recent accelerator projects at KEK, such as the Superconducting RF Test Facility (STF) for R and D of the International Linear Collider (ILC) project and the compact Energy Recovery Linac (cERL), employ superconducting RF cavities made of pure niobium, which can generate high gradient acceleration field. Since the operation temperature of these cavities is selected to be 2 K, we have developed two 2 K superfluid helium cryogenic systems for stable operation of superconducting RF cavities for each of STF and cERL. These two 2 K superfluid helium cryogenic systems are identical in principle. Since the operation mode of the cavities is different for STF and cERL, i.e. the pulse mode for STF and the continuous wave mode for cERL, the heat loads from the cavities are quite different. The 2 K superfluid helium cryogenic systems mainly consists of ordinary helium liquefiers/refrigerators, 2 K refrigerator cold boxes, helium gas pumping systems and high-performance transfer lines. The 2 K refrigerators and the high-performance transfer lines are designed by KEK. Some superconducting RF cavity cryomodules have been already connected to the 2 K superfluid helium cryogenic systems for STF and cERL respectively, and cooled down to 2 K successfully.

Nakai, H.; Hara, K.; Honma, T.; Hosoyama, K.; Kojima, Y.; Nakanishi, K. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0033 (Japan); Kanekiyo, T. [Hitachi Plant Technologies, Ltd., Toshima-ku, Tokyo 170-8466 (Japan); Morita, S. [Hitachi Plant Mechanics Co., Ltd., Kudamatsu, Yamaguchi 744-0061 (Japan)

2014-01-29T23:59:59.000Z

7

HOM Coupler Optimisation for the Superconducting RF Cavities in ESS  

E-Print Network [OSTI]

The European Spallation Source (ESS) will be the world’s most powerful next generation neutron source. It consists of a linear accelerator, target, and instruments for neutron experiments. The linac is designed to accelerate protons to a ?nal energy of 2.5 GeV, with an average design beam power of 5 MW, for collision with a target used to produce a high neutron ?ux. A section of the linac will contain Superconducting RF (SCRF) cavities designed at 704 MHz. Beam induced HOMs in these cavities may drive the beam unstable and increase the cryogenic load, therefore HOM couplers are installed to provide suf?cient damping. Previous studies have shown that these couplers are susceptible to multipacting, a resonant process which can absorb RF power and lead to heating effects. This paper will show how a coupler suffering from multipacting has been redesigned to limit this effect. Optimisation of the RF damping is also discussed.

Ainsworth, R; Calaga, R

2012-01-01T23:59:59.000Z

8

A new microphonics measurement method for superconducting RF cavities  

SciTech Connect (OSTI)

Mechanical vibrations of the superconducting cavity, also known as microphonics, cause shifts in the resonant frequency of the cavity. In addition to requiring additional RF power, these frequency shifts can contribute to errors in the closed loop phase and amplitude regulation. In order to better understand these effects, a new microphonics measurement method was developed, and the method was successfully used to measure microphonics on the half-wave superconducting cavity when it was operated in a production style cryostat. The test cryostat held a single ?=0.1 half-wave cavity which was operated at 162.5 MHz [1] and [2]. It's the first time that the National Instruments PXIe-5641R intermediate frequency transceiver has been used for microphonics measurements in superconducting cavities. The new microphonics measurement method and results will be shown and analyzed in this paper.

Gao,Zheng; He,Yuan; Chang,Wei; Powers, Tom [JLAB; Yue,Wei-ming; Zhu,Zheng-long; Chen,Qi

2014-09-01T23:59:59.000Z

9

Superconducting RF Linac Technology for ERL Light Sources  

SciTech Connect (OSTI)

Energy Recovering Linacs (ERLs) offer an attractive alternative as drivers for light sources as they combine the desirable characteristics of both storage rings (high efficiency) and linear accelerators (superior beam quality). Using superconducting RF technology allows ERLs to operate more efficiently because of the inherent characteristics of SRF linacs, namely that they are high gradient-low impedance structures and their ability to operate in the long pulse or CW regime. We present an overview of the physics challenges encountered in the design and operation of ERL based light sources with particular emphasis on those issues related to SRF technology. These challenges include maximizing a cavity�������¢����������������s Qo to increase cryogenic efficiency, maintaining control of the cavity field in the presence of the highest feasible loaded Q and providing adequate damping of the higher-order modes (HOMs). If not sufficiently damped, dipole HOMs can drive the multipass beam breakup (BBU) instability which ERLs are particularly susceptible to. Another challenge involves efficiently extracting the potentially large amounts of HOM power that are generated when a bunch traverses the SRF cavities and which may extend over a high range of frequencies. We present experimental data from the Jefferson Lab FEL Upgrade, a 10 mA ERL light source presently in operation, aimed at addressing some of these issues. We conclude with an outlook towards the future of ERL based light sources.

Chris Tennant

2005-08-01T23:59:59.000Z

10

Experimental Studies of Light Emission Phenomena in Superconducting RF Cavitites  

SciTech Connect (OSTI)

Experimental studies of light emission phenomena in superconducting RF cavities, which we categorize under the general heading of cavity lights, are described. The cavity lights data, which were obtained using a small CCD video camera, were collected in a series of nine experimental runs ranging from {approx} 1/2 to {approx} 2 h in duration. The video data were recorded on a standard VHS tape. As the runs progressed, additional instrumentation was added. For the last three runs a LabVIEW controlled data acquisition system was included. These runs furnish evidence for several, possibly related, light emission phenomena. The most intriguing of these is what appear to be small luminous objects {le} 1.5 mm in size, freely moving about in the vacuum space, generally without wall contact, as verified by reflections of the tracks in the cavity walls. In addition, on a number of occasions, these objects were observed to bounce off of the cavity walls. The wall-bounce aspect of most of these events was clearly confirmed by pre-bounce and post-bounce reflections concurrent with the tracks. In one of the later runs, a mode of behavior was observed that was qualitatively different from anything observed in the earlier runs. Perhaps the most perplexing aspect of this new mode was the observation of as many as seven luminous objects arrayed in what might be described as a macromolecular formation, coherently moving about in the interior of the cavity for extended periods of time, evidently without any wall contact. It is suggested that these mobile luminous objects are without explanation within the realm of established physics. Some remarks about more exotic theoretical possibilities are made, and future plans are discussed.

Anthony, P.L.; /SLAC; Delayen, J.R.; /Jefferson Lab; Fryberger, D.; /SLAC; Goree, W.S.; Mammosser, J.; /Jefferson Lab /SNS Project, Oak Ridge; Szalata, Z.M.; II, J.G.Weisend /SLAC

2009-08-04T23:59:59.000Z

11

First Characterization of a Fully Superconducting RF Photoinjector Cavity  

SciTech Connect (OSTI)

As a first step towards a high brightness, high average current electron source for the BERLinPro ERL a fully superconducting photo-injector was developed by HZB in collaboration with JLab, DESY and the A. Soltan Institute. This cavity-injector ensemble is made up of a 1.6-cell superconducting cavity with a superconducting lead cathode deposited on the half-cell backwall. A superconducting solenoid is used for emittance compensation. This system, including a diagnostics beamline, has been installed in the HoBiCaT facility to serve as a testbed for beam dynamics studies and to test the combination SRF cavity and superconducting solenoid. This paper summarizes the characterization of the cavity in this configuration including Q measurements, dark current tests and field-stability analyses.

Neumann, A; Barday, R; Jankowiak, A; Kamps, T; Knobloch, J; Kugeler, O; Matveenko, A N; Quast, T; Rudolph, J; Schubert, S G; Volker, J; Kneisel, P; Nietubyc, R; Sekutowicz, J K; Smedley, J; Volkov, V; Weinberg, G

2011-09-01T23:59:59.000Z

12

Capture cavity cryomodule for quantum beam experiment at KEK superconducting RF test facility  

SciTech Connect (OSTI)

A capture cavity cryomodule was fabricated and used in a beam line for quantum beam experiments at the Superconducting RF Test Facility (STF) of the High Energy Accelerator Research Organization in Japan. The cryomodule is about 4 m long and contains two nine-cell cavities. The cross section is almost the same as that of the STF cryomodules that were fabricated to develop superconducting RF cavities for the International Linear Collider. An attempt was made to reduce the large deflection of the helium gas return pipe (GRP) that was observed in the STF cryomodules during cool-down and warm-up. This paper briefly describes the structure and cryogenic performance of the captures cavity cryomodule, and also reports the measured displacement of the GRP and the cavity-containing helium vessels during regular operation.

Tsuchiya, K.; Hara, K.; Hayano, H.; Kako, E.; Kojima, Y.; Kondo, Y.; Nakai, H.; Noguchi, S.; Ohuchi, N.; Terashima, A. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Horikoshi, A.; Semba, T. [Hitachi, Ltd., Hitachi Works, Hitachi, Ibaraki 317-8511 (Japan)

2014-01-29T23:59:59.000Z

13

Superconducting RF Lab Facility Upgrades at Los Alamos  

SciTech Connect (OSTI)

Research and testing of multi-cell superconducting cavities demands extensive contamination control resources to achieve high-cavity fields. Facility upgrades at Los Alamos National Laboratory (LANL) included the modernization of test equipment, expanding and modernizing cleanroom facilities, improving safety, and expanding the high-pressure rinse cleaning process equipment. Each upgrade was integrated into the facility to enable users to assemble prototype cryomodules. The scope of the upgrades, the new installed capability, and budget and schedule for certain aspects of the project are discussed in this paper.

Katonak, D.J.; Rusnak, B.

1999-03-01T23:59:59.000Z

14

Superconducting RF cavity R&D for future accelerators  

E-Print Network [OSTI]

High-beta superconducting radiofrequency (SRF) elliptical cavities are being developed for several accelerator projects including Project X, the European XFEL, and the International Linear Collider (ILC). Fermilab has recently established an extensive infrastructure for SRF cavity R&D for future accelerators, including cavity surface processing and testing and cavity assembly into cryomodules. Some highlights of the global effort in SRF R&D toward improving cavity performance, and Fermilab SRF cavity R&D in the context of global projects are reviewed.

C. M. Ginsburg

2009-10-22T23:59:59.000Z

15

Construction and Test of a Novel Superconducting RF Electron gun  

SciTech Connect (OSTI)

The University of Wisconsin-Madison has completed installation of a superconducting electron gun. Its concept was optimized to be the source for a CW free electron laser facility with multiple megahertz repetition rate end stations. This VHF superconducting configuration holds the promise of the highest performance for CW injectors. Initial commissioning efforts show that the cavity can achieve gradients of 35 MV/m at the cathode position. With the cathode inserted CW operation has been achieved at 20 MV/m with good control of microphonics, negligible dark current, and Q0 > 3×109 at 4 K. Bunch charges of ~100 pC have been delivered, and first simple beam measurements made. These preliminary results are very encouraging for production of 100s pC bunches with millimeter-milliradian or smaller normalized emittances. Plans are in place to carry out more definitive studies to establish the full capabilities. However, since the grant was not renewed, the electron gun is currently mothballed, and without supplemental fund the opportunity for further work will be lost.

Bisognano, Joseph J. [University of Wisconsin-Madison] [University of Wisconsin-Madison

2014-04-16T23:59:59.000Z

16

Precision Vector Control of a Superconducting RF Cavity driven by an Injection Locked Magnetron  

E-Print Network [OSTI]

The technique presented in this paper enables the regulation of both radio frequency amplitude and phase in narrow band devices such as a Superconducting RF (SRF) cavity driven by constant power output devices i.e. magnetrons. The ability to use low cost high efficiency magnetrons for accelerator RF power systems, with tight vector regulation, presents a substantial cost savings in both construction and operating costs compared to current RF power system technology. An operating CW system at 2.45 GHz has been experimentally developed. Vector control of an injection locked magnetron has been extensively tested and characterized with a SRF cavity as the load. Amplitude dynamic range of 30 dB, amplitude stability of 0.3% r.m.s, and phase stability of 0.26 degrees r.m.s. has been demonstrated.

Chase, Brian; Cullerton, Ed; Varghese, Philip

2015-01-01T23:59:59.000Z

17

Precision Vector Control of a Superconducting RF Cavity driven by an Injection Locked Magnetron  

E-Print Network [OSTI]

The technique presented in this paper enables the regulation of both radio frequency amplitude and phase in narrow band devices such as a Superconducting RF (SRF) cavity driven by constant power output devices i.e. magnetrons. The ability to use low cost high efficiency magnetrons for accelerator RF power systems, with tight vector regulation, presents a substantial cost savings in both construction and operating costs compared to current RF power system technology. An operating CW system at 2.45 GHz has been experimentally developed. Vector control of an injection locked magnetron has been extensively tested and characterized with a SRF cavity as the load. Amplitude dynamic range of 30 dB, amplitude stability of 0.3% r.m.s, and phase stability of 0.26 degrees r.m.s. has been demonstrated.

Brian Chase; Ralph Pasquinelli; Ed Cullerton; Philip Varghese

2014-11-21T23:59:59.000Z

18

Design of a horizontal test cryostat for superconducting RF cavities for the FREIA facility at Uppsala University  

SciTech Connect (OSTI)

Uppsala University is constructing a large scale facility, called FREIA (Facility for Research Instrumentation and Accelerator Development). FREIA includes a helium liquefier and an accelerator test facility and has the capacity to test superconducting radio-frequency (RF) cavities with the same RF system and RF power level as in an accelerator. A central element of FREIA is a horizontal test cryostat connected in closed loop to a helium liquefier. This cryostat can house two fully equipped (tuners, piezo, power coupler, helium tank) superconducting cavities to perform full RF high power tests and operate at temperatures between 1.8 K and 4.2 K. The cryostat is designed to accommodate a large array of superconducting cavities and magnets, among which the European Spallation Source (ESS) type spoke and high-? elliptical cavities as well as TESLA/ILC type elliptical cavities. The present status of the project and the design of the cryostat are reported.

Chevalier, N. R.; Thermeau, J.-P.; Bujard, P.; Junquera, T. [Accelerators and Cryogenic Systems (ACS), 86 rue de Paris, 91400 Orsay (France); Hermansson, L.; Kern, R. Santiago; Ruber, R. [Uppsala University, Department of Physics and Astronomy, 75120 Uppsala (Sweden)

2014-01-29T23:59:59.000Z

19

A Survey of Pressure Vessel Code Compliance for Superconducting RF Cryomodules  

SciTech Connect (OSTI)

Superconducting radio frequency (SRF) cavities made from niobium and cooled with liquid helium are becoming key components of many particle accelerators. The helium vessels surrounding the RF cavities, portions of the niobium cavities themselves, and also possibly the vacuum vessels containing these assemblies, generally fall under the scope of local and national pressure vessel codes. In the U.S., Department of Energy rules require national laboratories to follow national consensus pressure vessel standards or to show ''a level of safety greater than or equal to'' that of the applicable standard. Thus, while used for its superconducting properties, niobium ends up being treated as a low-temperature pressure vessel material. Niobium material is not a code listed material and therefore requires the designer to understand the mechanical properties for material used in each pressure vessel fabrication; compliance with pressure vessel codes therefore becomes a problem. This report summarizes the approaches that various institutions have taken in order to bring superconducting RF cryomodules into compliance with pressure vessel codes. In Japan, Germany, and the U.S., institutions building superconducting RF cavities integrated in helium vessels or procuring them from vendors have had to deal with pressure vessel requirements being applied to SRF vessels, including the niobium and niobium-titanium components of the vessels. While niobium is not an approved pressure vessel material, data from tests of material samples provide information to set allowable stresses. By means of procedures which include adherence to code welding procedures, maintaining material and fabrication records, and detailed analyses of peak stresses in the vessels, or treatment of the vacuum vessel as the pressure boundary, research laboratories around the world have found methods to demonstrate and document a level of safety equivalent to the applicable pressure vessel codes.

Peterson, Thomas; Klebaner, Arkadiy; Nicol, Tom; Theilacker, Jay; /Fermilab; Hayano, Hitoshi; Kako, Eiji; Nakai, Hirotaka; Yamamoto, Akira; /KEK, Tsukuba; Jensch, Kay; Matheisen, Axel; /DESY; Mammosser, John; /Jefferson Lab

2011-06-07T23:59:59.000Z

20

Development of fundamental power coupler for high-current superconducting RF cavity  

SciTech Connect (OSTI)

Brookhaven National Laboratory took a project of developing a 704 MHz five-cell superconducting RF cavity for high-current linacs, including Energy Recovery Linac (ERL) for planned electron-hadron collider eRHIC. The cavity will be fed by a high-power RF amplifier using a coaxial Fundamental Power Coupler (FPC), which delivers 20 kW of CW RF power to the cavity. The design of FPC is one of the important aspects as one has to take into account the heat losses dissipated on the surface of the conductor by RF fields along with that of the static heat load. Using a simple simulation model we show the temperature profile and the heat load dissipated along the coupler length. To minimize the heat load on FPC near the cavity end, a thermal intercept is required at an appropriate location on FPC. A 10 K intercept was chosen and its location optimized with our simulation code. The requirement on the helium gas flow rate for the effective heat removal from the thermal intercept is also discussed.

Jain P.; Belomestnykh, S.; Ben-Zvi, I.; Xu, W.

2012-05-20T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Proc. of the workshop on pushing the limits of RF superconductivity.  

SciTech Connect (OSTI)

For three days in late September last year, some sixty experts in RF superconductivity from around the world came together at Argonne to discuss how to push the limits of RF superconductivity for particle accelerators. It was an intense workshop with in-depth presentations and ample discussions. There was added excitement due to the fact that, a few days before the workshop, the International Technology Recommendation Panel had decided in favor of superconducting technology for the International Linear Collider (ILC), the next major high-energy physics accelerator project. Superconducting RF technology is also important for other large accelerator projects that are either imminent or under active discussion at this time, such as the Rare Isotope Accelerator (RIA) for nuclear physics, energy recovery linacs (ERLs), and x-ray free-electron lasers. For these accelerators, the capability in maximum accelerating gradient and/or the Q value is essential to limit the length and/or operating cost of the accelerators. The technological progress of superconducting accelerators during the past two decades has been truly remarkable, both in low-frequency structures for acceleration of protons and ions as well as in high-frequency structures for electrons. The requirements of future accelerators demand an even higher level of performance. The topics of this workshop are therefore highly relevant and timely. The presentations given at the workshop contained authoritative reviews of the current state of the art as well as some original materials that previously had not been widely circulated. We therefore felt strongly that these materials should be put together in the form of a workshop proceeding. The outcome is this report, which consists of two parts: first, a collection of the scholarly papers prepared by some of the participants and second, copies of the viewgraphs of all presentations. The presentation viewgraphs, in full color, are also available from the Workshop Presentations link on the workshop's web page at http://www.aps.anl.gov/conferences/RFSCLimits/. I would like to thank all of the participants for their lively contributions to the workshop and to these proceedings, and Helen Edwards and Hasan Padamsee for their help in developing the workshop program. I also thank Cathy Eyberger, Kelly Jaje, and Renee Lanham for working very hard to take care of the administrative details, in particular Cathy for editing this report.

Kim, K-J., Eyberger, C., editors

2005-04-13T23:59:59.000Z

22

Conceptual Design for Replacement of the DTL and CCL with Superconducting RF Cavities in the Spallation Neutron Source Linac  

SciTech Connect (OSTI)

The Spallation Neutron Source Linac utilizes normal conducting RF cavities in the low energy section from 2.5 MeV to 186 MeV. Six Drift Tube Linac (DTL) structures accelerate the beam to 87 MeV, and four Coupled Cavity Linac (CCL) structures provide further acceleration to 186 MeV. The remainder of the Linac is comprised of 81 superconducting cavities packaged in 23 cryomodules to provide final beam energy of approximately 1 GeV. The superconducting Linac has proven to be substantially more reliable than the normal conducting Linac despite the greater number of stations and the complexity associated with the cryogenic plant and distribution. A conceptual design has been initiated on a replacement of the DTL and CCL with superconducting RF cavities. The motivation, constraints, and conceptual design are presented.

Champion, Mark S [ORNL] [ORNL; Doleans, Marc [ORNL] [ORNL; Kim, Sang-Ho [ORNL] [ORNL

2013-01-01T23:59:59.000Z

23

Plasma processing of large curved surfaces for superconducting rf cavity modification  

SciTech Connect (OSTI)

Plasma based surface modification of niobium is a promising alternative to wet etching of superconducting radio frequency (SRF) cavities. The development of the technology based on Cl2/Ar plasma etching has to address several crucial parameters which influence the etching rate and surface roughness, and eventually, determine cavity performance. This includes dependence of the process on the frequency of the RF generator, gas pressure, power level, the driven (inner) electrode configuration, and the chlorine concentration in the gas mixture during plasma processing. To demonstrate surface layer removal in the asymmetric non-planar geometry, we are using a simple cylindrical cavity with 8 ports symmetrically distributed over the cylinder. The ports are used for diagnosing the plasma parameters and as holders for the samples to be etched. The etching rate is highly correlated with the shape of the inner electrode, radio-frequency (RF) circuit elements, chlorine concentration in the Cl2/Ar gas mixtures, residence time of reactive species and temperature of the cavity. Using cylindrical electrodes with variable radius, large-surface ring-shaped samples and d.c. bias implementation in the external circuit we have demonstrated substantial average etching rates and outlined the possibility to optimize plasma properties with respect to maximum surface processing effect.

Upadhyay, J.; Im, Do; Popovi??, S.; Valente-Feliciano, A.-M.; Phillips, L.; Vuskovic, L

2014-12-01T23:59:59.000Z

24

Mechanical design of 56 MHz superconducting RF cavity for RHIC collider  

SciTech Connect (OSTI)

A 56 MHz Superconducting RF Cavity operating at 4.4K is being constructed for the RHIC collider. This cavity is a quarter wave resonator with beam transmission along the centerline. This cavity will increase collision luminosity by providing a large longitudinal bucket for stored bunches of RHIC ion beam. The major components of this assembly are the niobium cavity with the mechanical tuner, its titanium helium vessel and vacuum cryostat, the support system, and the ports for HOM and fundamental dampers. The cavity and its helium vessel must meet equivalent safety with the ASME pressure vessel code and it must not be sensitive to frequency shift due to pressure fluctuations from the helium supply system. Frequency tuning achieved by a two stage mechanical tuner is required to meet performance parameters. This tuner mechanism pushes and pulls the tuning plate in the gap of niobium cavity. The tuner mechanism has two separate drive systems to provide both coarse and fine tuning capabilities. This paper discusses the design detail and how the design requirements are met.

Pai, C.; Ben-Zvi, I.; Burrill, A.; Chang, X.; McIntyre, G.; Than, Y.; Tuozzolo, J.; Wu, Q.

2011-03-28T23:59:59.000Z

25

Detection of surface carbon and hydrocarbons in hot spot regions of niobium superconducting rf cavities by Raman spectroscopy  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Raman microscopy/spectroscopy measurements are presented on high purity niobium (Nb) samples, including pieces from hot spot regions of a tested superconducting rf cavity that exhibit a high density of etch pits. Measured spectra are compared with density functional theory calculations of Raman-active, vibrational modes of possible surface Nb-O and Nb-H complexes. The Raman spectra inside particularly rough pits in all Nb samples show clear differences from surrounding areas, exhibiting enhanced intensity and sharp peaks. While some of the sharp peaks are consistent with calculated NbH and NbH2 modes, there is better overall agreement with C-H modes in chain-type hydrocarbons. Other spectra reveal two broader peaks attributed to amorphous carbon. Niobium foils annealed to >2000°C in high vacuum develop identical Raman peaks when subjected to cold working. Regions with enhanced C and O have also been found by SEM/EDX spectroscopy in the hot spot samples and cold-worked foils, corroborating the Raman results. Such regions with high concentrations of impurities are expected to suppress the local superconductivity and this may explain the correlation between hot spots in superconducting rf (SRF) cavities and the observation of a high density of surface pits. The origin of localized high carbon and hydrocarbon regions is unclear at present but it is suggested that particular processing steps in SRF cavity fabrication may be responsible.

Cao, C.; Ford, D.; Bishnoi, S.; Proslier, T.; Albee, B.; Hommerding, E.; Korczakowski, A.; Cooley, L.; Ciovati, G.; Zasadzinski, J. F.

2013-06-01T23:59:59.000Z

26

Cold RF test and associated mechanical features correlation of a TESLA-style 9-cell superconducting niobium cavity built in China  

SciTech Connect (OSTI)

The RF performance of a 1.3 GHz 9-cell superconducting niobium cavity was evaluated at cryogenic temperatures following surface processing by using the standard ILC-style recipe. The cavity is a TESLA-style 9-cell superconducting niobium cavity, with complete end group components including a higher order mode coupler, built in China for practical applications. An accelerating gradient of 28.6 MV/m was achieved at an unloaded quality factor of 4 x 10{sup 9}. The morphological property of mechanical features on the RF surface of this cavity was characterized through optical inspection. Correlation between the observed mechanical features and the RF performance of the cavity is attempted.

Dai, Jing; Quan, Sheng-Wen; Zhang, Bao-Cheng; Lin, Lin; Hao, Jian-Kui; Zhu, Feng; Xu, Wen-Can; He, Fei-Si; Jin, Song; Wang, Fang; Liu, Ke-Xin; Geng, R L

2012-02-01T23:59:59.000Z

27

SUPERCONDUCTING RF STRUCTURES TEST FACILITIES AND H. Weise, Deutsches Elektronen-Synchrotron, Hamburg, Germany  

E-Print Network [OSTI]

-Synchrotron, Hamburg, Germany for the TESLA Collaboration Abstract The design of the TESLA superconducting electron than 16 thousand hours of operation demonstrated this technology. Results of single cavity tests followed by drying in a class 100 clean room; annealing at 800°C in an Ultra High Vacuum oven to relieve

28

Proposal to negotiate a collaboration agreement related to the application of novel cavity fabrication techniques and Nb/Cu sputter coating technology in the field of superconducting RF for the Future Circular Collider (FCC) study  

E-Print Network [OSTI]

Proposal to negotiate a collaboration agreement related to the application of novel cavity fabrication techniques and Nb/Cu sputter coating technology in the field of superconducting RF for the Future Circular Collider (FCC) study

2015-01-01T23:59:59.000Z

29

The Design of a Five-Cell Superconducting RF Module with a PBG Coupler Cell  

SciTech Connect (OSTI)

We discuss the problem of incorporating a Photonic Band Gap (PBG) cell into a superconducting accelerating module of 5 cells designed for the operational frequency of 2.1 GHz. The reason for using a PBG cell is to provide a good accelerating mode confinement and good Higher Order Mode (HOM) suppression. PBG cell can potentially be used for placing HOM and fundamental mode couplers. However, because of the naturally higher ratio of the peak magnetic field to the accelerating field in the PBG cell, it should be designed to operate at a lower accelerating gradient than the other cells of the module. This ensures that the probability of quench in the PBG cell would be no higher than in other elliptical cells of the structure.

Arsenyev, Sergey A [Los Alamos National Laboratory; Simakov, Evgenya I [Los Alamos National Laboratory

2012-08-29T23:59:59.000Z

30

Comparative Simulation Studies of Multipacting in Higher-Order-Mode Couplers of Superconducting RF Cavities  

SciTech Connect (OSTI)

Multipacting (MP) in higher-order-mode (HOM) couplers of the International Linear Collider (ILC) baseline cavity and the Continuous Electron Beam Accelerator Facility (CEBAF) 12 GeV upgrade cavity is studied by using the ACE3P suites, developed by the Advanced Computations Department at SLAC. For the ILC cavity HOM coupler, the simulation results show that resonant trajectories exist in three zones, corresponding to an accelerating gradient range of 0.6?1.6 MV/m, 21?34 MV/m, 32?35 MV/m, and > 40MV/m, respectively. For the CEBAF 12 GeV upgrade cavity HOM coupler, resonant trajectories exist in one zone, corresponding to an accelerating gradient range of 6?13 MV/m. Potential implications of these MP barriers are discussed in the context of future high energy pulsed as well as medium energy continuous wave (CW) accelerators based on superconducting radio frequency cavities. Frequency scaling of MP?s predicted in HOM couplers of the ILC, CBEAF upgrade, SNS and FLASH third harmonic cavity is given and found to be in good agreement with the analytical result based on the parallel plate model.

Li, Y. M. [Peking University, Beijing (China); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Liu, Kexin [Peking University, Beijing (China); Geng, Rongli [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2014-02-01T23:59:59.000Z

31

Nanofabrication  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Regionat Cornell Batteries & FuelTechnologiesIndustrial

32

nanofabricaTion A Resource for Nanoscience  

E-Print Network [OSTI]

The nanofabricaTion cenTer A Resource for Nanoscience and Technology WorKinG WiTh US be appropriate. These projects are directed to more fundamental nanoscience issues, and provide a basis

Blanchette, Robert A.

33

Advanced nanofabrication of thermal emission devices  

E-Print Network [OSTI]

Nanofabricated thermal emission devices can be used to modify and modulate blackbody thermal radiation. There are many areas in which altering thermal radiation is extremely useful, especially in static power conversion, ...

Hurley, Fergus (Fergus Gerard)

2008-01-01T23:59:59.000Z

34

Micro/nanofabricated environments for synthetic biology  

SciTech Connect (OSTI)

A better understanding of how confinement, crowding and reduced dimensionality modulate reactivity and reaction dynamics will aid in the rational and systematic discovery of functionality in complex biological systems. Artificial micro- and nanofabricated structures have helped elucidate the effects of nanoscale spatial confinement and segregation on biological behavior, particularly when integrated with microfluidics, through precise control in both space and time of diffusible signals and binding interactions. Examples of nanostructured interfaces for synthetic biology include the development of cell-like compartments for encapsulating biochemical reactions, nanostructured environments for fundamental studies of diffusion, molecular transport and biochemical reaction kinetics, and regulation of biomolecular interactions as functions of micro- and nanofabricated topological constraints.

Collier, Pat [ORNL; Simpson, Michael L [ORNL

2011-01-01T23:59:59.000Z

35

analog rf gap: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

LHC, particles not captured by the RF system at injection or leaking out of the RF bucket may quench the superconducting magnets during beam abort. The problem, common to other...

36

Nanofabrication on unconventional substrates using transferred hard masks  

E-Print Network [OSTI]

A major challenge in nanofabrication is to pattern unconventional substrates that cannot be processed for a variety of reasons, such as incompatibility with spin coating, electron beam lithography, optical lithography, or ...

Li, Luozhou

37

Nanofabrication of Diffractive X-ray Optics for Synchrotrons...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nanofabrication of Diffractive X-ray Optics for Synchrotrons and XFELs Wednesday, March 11, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Christian David, Paul...

38

Superconducting microfabricated ion traps  

E-Print Network [OSTI]

We fabricate superconducting ion traps with niobium and niobium nitride and trap single 88Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the resistance and critical current using a 4-wire measurement on the trap structure, and observing change in the rf reflection. The lowest observed heating rate is 2.1(3) quanta/sec at 800 kHz at 6 K and shows no significant change across the superconducting transition, suggesting that anomalous heating is primarily caused by noise sources on the surface. This demonstration of superconducting ion traps opens up possibilities for integrating trapped ions and molecular ions with superconducting devices.

Shannon X. Wang; Yufei Ge; Jaroslaw Labaziewicz; Eric Dauler; Karl Berggren; Isaac L. Chuang

2010-12-14T23:59:59.000Z

39

Characterization of superconducting radiofrequency breakdown by two-mode excitation  

SciTech Connect (OSTI)

We show that thermal and magnetic contributions to the breakdown of superconductivity in radiofrequency (RF) fields can be separated by applying two RF modes simultaneously to a superconducting surface. We develop a simple model that illustrates how mode-mixing RF data can be related to properties of the superconductor. Within our model the data can be described by a single parameter, which can be derived either from RF or thermometry data. Our RF and thermometry data are in good agreement with the model. We propose to use mode-mixing technique to decouple thermal and magnetic effects on RF breakdown of superconductors.

Eremeev, Grigory V. [JLAB, Newport News, VA (United States); Palczewski, Ari D. [JLAB, Newport News, VA (United States)

2014-01-01T23:59:59.000Z

40

WAFER TEST CAVITY -Linking Surface Microstructure to RF Performance: a ‘Short-­?Sample Test Facility’ for characterizing superconducting materials for SRF cavities.  

SciTech Connect (OSTI)

The Wafer Test cavity was designed to create a short sample test system to determine the properties of the superconducting materials and S?I?S hetero?structures. The project, funded by ARRA, was successful in accomplishing several goals to achieving a high gradient test system for SRF research and development. The project led to the design and construction of the two unique cavities that each severed unique purposes: the Wafer test Cavity and the Sapphire Test cavity. The Sapphire Cavity was constructed first to determine the properties of large single crystal sapphires in an SRF environment. The data obtained from the cavity greatly altered the design of the Wafer Cavity and provided the necessary information to ascertain the Wafer Test cavity’s performance.

Pogue, Nathaniel; Comeaux, Justin; McIntyre, Peter

2014-05-30T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Superconducting Magnets for Particle Accelerators  

E-Print Network [OSTI]

Superconductivity has been the most influential technology in the field of accelerators in the last 30 years. Since the commissioning of the Tevatron, which demonstrated the use and operability of superconductivity on a large scale, superconducting magnets and rf cavities have been at the heart of all new large accelerators. Superconducting magnets have been the invariable choice for large colliders, as well as cyclotrons and large synchrotrons. In spite of the long history of success, superconductivity remains a difficult technology, requires adequate R&D and suitable preparation, and has a relatively high cost. Hence, it is not surprising that the development has also been marked by a few setbacks. This article is a review of the main superconducting accelerator magnet projects; it highlights the main characteristics and main achievements, and gives a perspective on the development of superconducting magnets for the future generation of very high energy colliders.

Rossi, L

2012-01-01T23:59:59.000Z

42

SUPERCONDUCTING DEVICES  

E-Print Network [OSTI]

on all aspects of superconducting devices. IEEE Trans.on all aspects vf superconducting devices. The IBM JournalJ. Matisoo, The Superconducting Computer," Scientific

Clarke, John

2014-01-01T23:59:59.000Z

43

SPL RF Coupler Cooling Efficiency  

E-Print Network [OSTI]

Energy saving is an important challenge in accelerator design. In this framework, reduction of heat loads in a cryomodule is of fundamental importance due to the small thermodynamic efficiency of cooling at low temperatures. In particular, care must be taken during the design of its critical components (e.g. RF couplers, coldwarm transitions). In this framework, the main RF coupler of the Superconducting Proton Linac (SPL) cryomodule at CERN will not only be used for RF powering but also as the main mechanical support of the superconducting cavities. These two functions have to be accomplished while ensuring the lowest heat in-leak to the helium bath at 2 K. In the SPL design, the RF coupler outer conductor is composed of two walls and cooled by forced convection with helium gas at 4.5 K. Analytical, semi-analytical and numerical analyses are presented in order to defend the choice of gas cooling. Temperature profiles and thermal performance have been evaluated for different operating conditions; a sensitivit...

Bonomi, R; Montesinos, E; Parma, V; Vande Craen, A

2014-01-01T23:59:59.000Z

44

Upgrade of the cryogenic CERN RF test facility  

SciTech Connect (OSTI)

With the large number of superconducting radiofrequency (RF) cryomodules to be tested for the former LEP and the present LHC accelerator a RF test facility was erected early in the 1990’s in the largest cryogenic test facility at CERN located at Point 18. This facility consisted of four vertical test stands for single cavities and originally one and then two horizontal test benches for RF cryomodules operating at 4.5 K in saturated helium. CERN is presently working on the upgrade of its accelerator infrastructure, which requires new superconducting cavities operating below 2 K in saturated superfluid helium. Consequently, the RF test facility has been renewed in order to allow efficient cavity and cryomodule tests in superfluid helium and to improve its thermal performances. The new RF test facility is described and its performances are presented.

Pirotte, O.; Benda, V.; Brunner, O.; Inglese, V.; Maesen, P.; Vullierme, B. [CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Koettig, T. [ESS - European Spallation Source, Box 176, 221 00 Lund (Sweden)

2014-01-29T23:59:59.000Z

45

SUPERCONDUCTING DEVICES  

E-Print Network [OSTI]

communications. References Superconductor Applications: ~on all aspects of superconducting devices. IEEE Trans.on all aspects vf superconducting devices. The IBM Journal

Clarke, John

2014-01-01T23:59:59.000Z

46

Superconducting RF, the History, Challenges and Promise  

SciTech Connect (OSTI)

After a short survey of on-going accelerator applications, I will discuss future applications prospects for this enabling technology, both near term and long term. A selection of technology highlights will serve as an introduction to outstanding issues for all types of applications, from pulsed high gradient to CW medium gradient. Finally I will touch upon the limits of niobium and the prospects of new materials. The talk will be targeted at a general audience.

Hasan Padamsee

2009-11-18T23:59:59.000Z

47

Superconducting RF, the History, Challenges and Promise  

ScienceCinema (OSTI)

After a short survey of on-going accelerator applications, I will discuss future applications prospects for this enabling technology, both near term and long term. A selection of technology highlights will serve as an introduction to outstanding issues for all types of applications, from pulsed high gradient to CW medium gradient. Finally I will touch upon the limits of niobium and the prospects of new materials. The talk will be targeted at a general audience.

Hasan Padamsee

2010-01-08T23:59:59.000Z

48

Superconductive wire  

DOE Patents [OSTI]

A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity.

Korzekwa, David A. (Los Alamos, NM); Bingert, John F. (Jemez Springs, NM); Peterson, Dean E. (Los Alamos, NM); Sheinberg, Haskell (Santa Fe, NM)

1995-01-01T23:59:59.000Z

49

Recycler barrier RF buckets  

SciTech Connect (OSTI)

The Recycler Ring at Fermilab uses a barrier rf systems for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf system, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.

Bhat, C.M.; /Fermilab

2011-03-01T23:59:59.000Z

50

CONFIRMATION NO. 1357 SESSION ID 3EI07 1 Fabrication and characterization of superconducting  

E-Print Network [OSTI]

CONFIRMATION NO. 1357 SESSION ID 3EI07 1 Fabrication and characterization of superconducting-angle evaporation in superconducting resonators with high quality factor. An important issue is to characterize the quality factor of the res- onators. We present an RF-characterization of superconducting resonators

51

Study of AC/RF properties of SRF ingot niobium  

SciTech Connect (OSTI)

In an attempt to correlate the performance of superconducting radiofrequency cavities made of niobium with the superconducting properties, we present the results of the magnetization and ac susceptibility of the niobium used in the superconducting radiofrequency cavity fabrication. The samples were subjected to buffer chemical polishing (BCP) surface and high temperature heat treatments, typically applied to the cavities fabrications. The analysis of the results show the different surface and bulk ac conductivity for the samples subjected to BCP and heat treatment. Furthermore, the RF surface impedance is measured on the sample using a TE011 microwave cavity for a comparison to the low frequency measurements.

Dhakal, Pashupati; Tsindlekht, Menachem I.; Genkin, Valery M.; Ciovati, Gianluigi; Myneni, Ganapati Rao

2013-09-01T23:59:59.000Z

52

Beam dynamics studies for transverse electromagnetic mode type rf deflectors  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We have performed three-dimensional simulations of beam dynamics for transverse electromagnetic mode (TEM) type rf deflectors: normal and superconducting. The compact size of these cavities as compared to the conventional TM110 type structures is more attractive particularly at low frequency. Highly concentrated electromagnetic fields between the parallel bars provide strong electrical stability to the beam for any mechanical disturbance. An array of six 2-cell normal conducting cavities or a single cell superconducting structure is enough to produce the required vertical displacement at the target point. Both the normal and superconducting structures show very small emittance dilution due to the vertical kick of the beam.

Ahmed, Shahid; Krafft, Geoffrey A.; Deitrick, Kirsten; De Silva, Subashini U.; Delayen, Jean R.; Spata, Mike; Tiefenback, Michael; Hofler, Alicia; Beard, Kevin

2012-02-01T23:59:59.000Z

53

RF power recovery feedback circulator  

DOE Patents [OSTI]

A device and method for improving the efficiency of RF systems having a Reflective Load. In the preferred embodiment, Reflected Energy from a superconducting resonator of a particle accelerator is reintroduced to the resonator after the phase of the Reflected Energy is aligned with the phase of the Supply Energy from a RF Energy Source. In one embodiment, a Circulator is used to transfer Reflected Energy from the Reflective Load into a Phase Adjuster which aligns the phase of the Reflected Energy with that of the Supply Energy. The phase-aligned energy is then combined with the Supply Energy, and reintroduced into the Reflective Load. In systems having a constant phase shift, the Phase Adjuster may be designed to shift the phase of the Reflected Energy by a constant amount using a Phase Shifter. In systems having a variety (variable) phase shifts, a Phase Shifter controlled by a phase feedback loop comprising a Phase Detector and a Feedback Controller to account for the various phase shifts is preferable.

Sharamentov, Sergey I. (Bolingbrook, IL)

2011-03-29T23:59:59.000Z

54

Superconducting Cable  

DOE Patents [OSTI]

In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

2005-07-22T23:59:59.000Z

55

Superconducting Cable  

DOE Patents [OSTI]

In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

2005-03-08T23:59:59.000Z

56

R&D ERL: High power RF systems  

SciTech Connect (OSTI)

The Energy Recovery Linac (ERL) project, now under construction at Brookhaven National Laboratory, requires two high power RF systems. The first RF system is for the 703.75 MHz superconducting electron gun. The RF power from this system is used to drive nearly half an Ampere of beam current to 2.5 MeV. There is no provision to recover any of this energy so the minimum amplifier power is 1 MW. It consists of 1 MW CW klystron, transmitter and power supplies, 1 MW circulator, 1 MW dummy load and a two-way power splitter. The second RF system is for the 703.75 MHz superconducting cavity. The system accelerates the beam to 54.7 MeV and recovers this energy. It will provide up to 50 kW of CW RF power to the cavity. It consists of 50 kW transmitter, circulator, and dummy load. This paper describes the two high power RF systems and presents the test data for both.

Zaltsman, A.

2010-01-15T23:59:59.000Z

57

High power RF systems for the BNL ERL project  

SciTech Connect (OSTI)

The Energy Recovery Linac (ERL) project, now under construction at Brookhaven National Laboratory, requires two high power RF systems. The first RF system is for the 703.75 MHz superconducting electron gun. The RF power from this system is used to drive nearly half an Ampere of beam current to 2 MeV. There is no provision to recover any of this energy so the minimum amplifier power is 1 MW. It consists of 1 MW CW klystron, transmitter and power supplies, 1 MW circulator, 1 MW dummy load and a two-way power splitter. The second RF system is for the 703.75 MHz superconducting cavity. The system accelerates the beam to 54.7 MeV and recovers this energy. It will provide up to 50 kW of CW RF power to the cavity. It consists of 50 kW transmitter, circulator, and dummy load. This paper describes the two high power RF systems and presents the test data for both.

Zaltsman, A.; Lambiase, R.

2011-03-28T23:59:59.000Z

58

Rf Feedback free electron laser  

DOE Patents [OSTI]

A free electron laser system and electron beam system for a free electron laser which use rf feedback to enhance efficiency. Rf energy is extracted from an electron beam by decelerating cavities and returned to accelerating cavities using rf returns such as rf waveguides, rf feedthroughs, etc. This rf energy is added to rf klystron energy to lower the required input energy and thereby enhance energy efficiency of the system.

Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

59

Superconducting structure  

DOE Patents [OSTI]

A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

Kwon, Chuhee (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

2003-04-01T23:59:59.000Z

60

Superconducting Structure  

DOE Patents [OSTI]

A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

Kwon, Chuhee (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

2005-09-13T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Rf System Requirements for JLab’s MEIC Collider Ring  

SciTech Connect (OSTI)

The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. At the top energy are the electron and ion collider rings. For the ion ring, it accelerates five long ion bunches to colliding energy and rebunches ions into a train of very short bunches before colliding. A set of low frequency RF system is needed for the long ion bunch energy ramping. Another set of high frequency RF cavities is needed to rebunch ions. For the electron ring, superconducting RF (SRF) cavities are needed to compensate the synchrotron radiation energy loss. The impedance of the SRF cavities must be low enough to keep the high current electron beam stable. The preliminary design requirements of these RF cavities are presented.

Wang, Shaoheng [JLAB; Li, Rui [JLAB; Rimmer, Robert A. [JLAB; Wang, Haipeng [JLAB; Zhang, Yuhong [JLAB

2013-06-01T23:59:59.000Z

62

ANALYZING SURFACE ROUGHNESS DEPENDENCE OF LINEAR RF LOSSES  

SciTech Connect (OSTI)

Topographic structure on Superconductivity Radio Frequency (SRF) surfaces can contribute additional cavity RF losses describable in terms of surface RF reflectivity and absorption indices of wave scattering theory. At isotropic homogeneous extent, Power Spectrum Density (PSD) of roughness is introduced and quantifies the random surface topographic structure. PSD obtained from different surface treatments of niobium, such Buffered Chemical Polishing (BCP), Electropolishing (EP), Nano-Mechanical Polishing (NMP) and Barrel Centrifugal Polishing (CBP) are compared. A perturbation model is utilized to calculate the additional rough surface RF losses based on PSD statistical analysis. This model will not consider that superconductor becomes normal conducting at fields higher than transition field. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range from linear loss mechanisms.

Reece, Charles E. [JLAB; Kelley, Michael J. [JLAB, W& M College; Xu, Chen [JLAB, W& M College

2012-09-01T23:59:59.000Z

63

Advanced RF power sources for linacs  

SciTech Connect (OSTI)

In order to maintain a reasonable over-all length at high center-of-mass energy, the main linac of an electron-positron linear collider must operate at a high accelerating gradient. For copper (non-superconducting) accelerator structures, this implies a high peak power per unit length and a high peak power per RF source, assuming a limited number of discrete sources are used. To provide this power, a number of devices are currently under active development or conceptual consideration: conventional klystrons with multi-cavity output structures, gyroklystrons, magnicons, sheet-beam klystrons, multiple-beam klystrons and amplifiers based on the FEL principle. To enhance the peak power produced by an rf source, the SLED rf pulse compression scheme is currently in use on existing linacs, and new compression methods that produce a flatter output pulse are being considered for future linear colliders. This paper covers the present status and future outlook for the more important rf power sources and pulse compression systems. It should be noted that high gradient electron linacs have applications in addition to high-energy linear colliders; they can, for example, serve as compact injectors for FEL`s and storage rings.

Wilson, P.B.

1996-10-01T23:59:59.000Z

64

Superconducting phase qubits  

E-Print Network [OSTI]

frequency noise in dc superconducting quantum interfer- enceeld enhancement of superconductivity in ultranarrow wires.Transformed dissipation in superconducting quantum circuits.

Martinis, John M.

2009-01-01T23:59:59.000Z

65

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

and R. W . BOOIll, "Superconductive Energy Storage Inducand H. A. Peterson, "Superconductive E nergy S torage forMeeting, Janua ry N. Mohan, "Superconductive Energy S torage

Hassenzahl, W.

2011-01-01T23:59:59.000Z

66

Superconducting phase qubits  

E-Print Network [OSTI]

frequency noise in dc superconducting quantum interfer- enceTransformed dissipation in superconducting quantum circuits.two-level system noise in superconducting microreson- ators.

Martinis, John M.

2009-01-01T23:59:59.000Z

67

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

Design of the BPA Superconducting 30-MJ Energy Storagefor a Utility Scale Superconducting Magnetic Energy Storagefor a Lnrge Scale Superconducting Magnetic Energy Storage

Hassenzahl, W.

2011-01-01T23:59:59.000Z

68

Development of an RF Conditioning System for Charged-Particle Accelerators  

SciTech Connect (OSTI)

Charged-particle accelerators use various vacuum windows on their accelerating radio-frequency (RF) cavities to throughput very high RF power. Before being placed on the cavities, the windows should be cleaned, baked, and fully RF conditioned to prevent a poor vacuum from outgassing, as well as other forms of contamination. An example is the coaxial fundamental power coupler (FPC) with an annular alumina ceramic window for each of the 81 superconducting RF cavities in the Spallation Neutron Source (SNS) linear accelerator. The FPCs needed to be tested up to 650-kW peak in a traveling wave and 2.6 MW with standing wave peaks in 1.3 and 60 pulses/s at 805 MHz. In this paper, an Experimental-Physics-and-Industrial-Control-System-based RF conditioning system for the SNS RF test facility is presented. This paper summarizes the hardware and software design strategies, provides the results obtained, and describes the future research scope.

Kang, Yoon W [ORNL; Howlader, Mostofa [ORNL; Shajedul Hasan, Dr. S. M. [Virginia Polytechnic Institute and State University (Virginia Tech)

2008-01-01T23:59:59.000Z

69

CFN Operations and Safety Awareness (COSA) Checklist Nanofabrication (Clean Room) Facility  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route SegmentsCleanNanofabrication (Clean Room)

70

COMPARISON OF RF CAVITY TRANSPORT MODELS FOR BBU SIMULATIONS  

SciTech Connect (OSTI)

The transverse focusing effect in RF cavities plays a considerable role in beam dynamics for low-energy beamline sections and can contribute to beam breakup (BBU) instability. The purpose of this analysis is to examine RF cavity models in simulation codes which will be used for BBU experiments at Jefferson Lab and improve BBU simulation results. We review two RF cavity models in the simulation codes elegant and TDBBU (a BBU simulation code developed at Jefferson Lab). elegant can include the Rosenzweig-Serafini (R-S) model for the RF focusing effect. Whereas TDBBU uses a model from the code TRANSPORT which considers the adiabatic damping effect, but not the RF focusing effect. Quantitative comparisons are discussed for the CEBAF beamline. We also compare the R-S model with the results from numerical simulations for a CEBAF-type 5-cell superconducting cavity to validate the use of the R-S model as an improved low-energy RF cavity transport model in TDBBU. We have implemented the R-S model in TDBBU. It will improve BBU simulation results to be more matched with analytic calculations and experimental results.

Ilkyoung Shin,Byung Yunn,Todd Satogata,Shahid Ahmed

2011-03-01T23:59:59.000Z

71

Theory and Practice of Cavity RF Test Systems  

SciTech Connect (OSTI)

Over the years Jefferson Lab staff members have performed about 2500 cold cavity tests on about 500 different superconducting cavities. Most of these cavities were later installed in 73 different cryomodules, which were used in three different accelerators. All of the cavities were tested in our vertical test area. About 25% of the cryomodules were tested in our cryomodule test facility and later commissioned in an accelerator. The remainder of the cryomodules were tested and commissioned after they were installed in their respective accelerator. This paper is an overview which should provide a practical background in the RF systems used to test the cavities as well as provide the mathematics necessary to convert the raw pulsed or continuous wave RF signals into useful information such as gradient, quality factor, RF-heat loads and loaded Q?s. Additionally, I will provide the equations necessary for determining the measurement error associated with these values.

Tom Powers

2006-08-28T23:59:59.000Z

72

Comparison of electromagnetic, thermal and mechanical calculations with rf test results in rf-dipole deflecting/crabbing cavities  

SciTech Connect (OSTI)

The current requirements of higher gradients and strict dimensional constraints in the emerging applications have required the designing of compact deflecting and crabbing rf structures. The superconducting rf-dipole cavity is one of the first novel compact designs with attractive properties such as higher gradients, higher shunt impedance and widely separated higher order modes. The recent tests performed on proof-of-principle designs of the rf-dipole geometry at 4.2 K and 2.0 K in the vertical test area at Jefferson Lab have proven the designs to achieve higher gradients with higher intrinsic quality factors and easily processed multipacting conditions. The cavity characteristics, such as pressure sensitivity and Lorentz force detuning, were studied using ANSYS before the fabrication. These characteristics were measured during the cavity test. The comparison between the simulation and the measurement provides insight how the simulation can be used for design and fabrication of future cavities.

Park, HyeKyoung [JLAB, ODU; De Silva, Subashini U. [ODU; Delayen, Jean R. [ODU, JLAB

2013-12-01T23:59:59.000Z

73

RF CONTROL REQUIREMENTS FOR THE CEBAF ENERGY UPGRADE C. Hovater, J. Delayen, L. Merminga, T. Powers, C. Reece, Jefferson Lab, Newport News, VA  

E-Print Network [OSTI]

RF CONTROL REQUIREMENTS FOR THE CEBAF ENERGY UPGRADE CAVITIES* C. Hovater, J. Delayen, L. Merminga, T. Powers, C. Reece, Jefferson Lab, Newport News, VA Abstract The 6 GeV CEBAF accelerator superconducting cavity for the CEBAF and FEL upgrades. From the low-level RF (LLRF) controls perspective higher

74

Nuclear magnetic resonance apparatus having semitoroidal rf coil for use in topical NMR and NMR imaging  

DOE Patents [OSTI]

An improved nuclear magnetic resonance (NMR) apparatus for use in topical magnetic resonance (TMR) spectroscopy and other remote sensing NMR applications includes a semitoroidal radio-frequency (rf) coil. The semitoroidal rf coil produces an effective alternating magnetic field at a distance from the poles of the coil, so as to enable NMR measurements to be taken from selected regions inside an object, particularly including human and other living subjects. The semitoroidal rf coil is relatively insensitive to magnetic interference from metallic objects located behind the coil, thereby rendering the coil particularly suited for use in both conventional and superconducting NMR magnets. The semitoroidal NMR coil can be constructed so that it emits little or no excess rf electric field associated with the rf magnetic field, thus avoiding adverse effects due to dielectric heating of the sample or to any other interaction of the electric field with the sample.

Fukushima, Eiichi (Los Alamos, NM); Roeder, Stephen B. W. (La Mesa, CA); Assink, Roger A. (Albuquerque, NM); Gibson, Atholl A. V. (Bryan, TX)

1986-01-01T23:59:59.000Z

75

Can RF help CMOS processors?  

E-Print Network [OSTI]

FOR C OMMUNICATIONS Can RF Help CMOS Processors? Eran SocherRF communication can help increase the wired communicationaluminum and low-K dielectrics help reduce wire delay but do

Socher, Eran; Chang, Mau-Chung Frank

2007-01-01T23:59:59.000Z

76

Superconducting Magnet Division  

E-Print Network [OSTI]

Superconducting Magnet Division DOE NP Program Review - July 06 1 Brookhaven Magnet Division - Nuclear Physics Program Support Activities Superconducting Magnet Program RHIC Operations Support Spin Summary Peter Wanderer, DOE review, July 25, 2006 Acting Head, Superconducting Magnet Division #12

77

RF test bench automation Description  

E-Print Network [OSTI]

RF test bench automation Description: Callisto would like to implement automated RF test bench. Three RF test benches have to be studied and automated: LNA noise temperature test bench LNA gain phase of the test benches and an implementation of the automation phase. Tasks: Noise temperature

Dobigeon, Nicolas

78

805 MHz and 201 MHz RF cavity development for MUCOOL  

SciTech Connect (OSTI)

A muon cooling channel calls for very high acceleratinggradient RF structures to restore the energy lost by muons in theabsorbers. The RF structures have to be operated in a strong magneticfield and thus the use of superconducting RF cavities is excluded. Toachieve a high shunt impedance while maintaining a large enough apertureto accommodate a large transverse emittance muon beam, the cavity designadopted is a pillbox-like geometry with thin Be foils to terminate theelectromagnetic field at the cavity iris. The possibility of using gridsof thin-walled metallic tubes for the termination is also being explored.Many of the RF-related issues for muon cooling channels are being studiedboth theoretically and experimentally using an 805 MHz cavity that has apillbox-like geometry with thin Be windows to terminate the cavityaperture. The design and performance of this cavity are reported here.High-power RF tests of the 805 MHz cavity are in progress at Lab G inFermilab. The cavity has exceeded its design gradient of 30 MV/m,reaching 34 MV/m without external magnetic field. No surface damage wasobserved at this gradient. The cavity is currently under conditioning atLab G with an external magnetic field of 2.5 T. We also present here a201 MHz cavity design for muoncooling channels. The proposed cavitydesign is also suitable for use in a proof-of-principle Muon IonizationCooling Experiment (MICE).

DLi@lbl.gov

2002-10-10T23:59:59.000Z

79

CAMD Nanofabrication  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone6Energy, science, and technologyVisitorsC.Request User

80

CAMD Nanofabrication  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route Segments (notCAMD Cleanroom ChemicalHome ::

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Superconducting Topological Insulators  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Superconducting Topological Insulators Superconducting Topological Insulators Print Wednesday, 26 January 2011 00:00 Three-dimensional topological insulators (TIs), discovered...

82

(Final Draft) Superconducting  

E-Print Network [OSTI]

ANDAND (Final Draft) Achieving Advanced Electrical Wires From Superconducting Coatings Prepared and Development Roadmap to Achieve Electrical Wire Advancements from Superconducting Coatings (Final Draft) Edited

83

SUPERCONDUCTING MAGNETIC ENERGY STORAGE  

E-Print Network [OSTI]

Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances

Hassenzahl, W.

2011-01-01T23:59:59.000Z

84

PERFORMANCE STATUS OF THE RF-GUN BASED INJECTOR OF THE TESLA TEST FACILITY LINAC  

E-Print Network [OSTI]

PERFORMANCE STATUS OF THE RF-GUN BASED INJECTOR OF THE TESLA TEST FACILITY LINAC S. Schreiber£ for the TESLA Collaboration, DESY, 22603 Hamburg, Germany Abstract The TESLA Test Facility Linac (TTFL) at DESY uses two modules with 8 TESLA superconducting accelerat- ing structures each to accelerate an electron

85

FIRST EXPERIMENTS WITH THE RF GUN BASED INJECTOR FOR THE TESLA TEST FACILITY LINAC  

E-Print Network [OSTI]

FIRST EXPERIMENTS WITH THE RF GUN BASED INJECTOR FOR THE TESLA TEST FACILITY LINAC S. Schreiber for the TESLA Collaboration, DESY, 22603 Hamburg, Germany Abstract During 1997 and 1998 a first accelerator module was tested successfully at the TESLA Test Facility Linac (TTFL) at DESY. Eight superconducting

86

Comparison of Measured and Calculated Coupling between a Waveguide and an RF Cavity Using CST Microwave Studio  

SciTech Connect (OSTI)

Accurate predications of RF coupling between an RF cavity and ports attached to it have been an important study subject for years for RF coupler and higher order modes (HOM) damping design. We report recent progress and a method on the RF coupling simulations between waveguide ports and RF cavities using CST Microwave Studio in time domain (Transit Solver). Comparisons of the measured and calculated couplings are presented. The simulated couplings and frequencies agree within {approx} 10% and {approx} 0.1% with the measurements, respectively. We have simulated couplings with external Qs ranging from {approx} 100 to {approx} 100,000, and confirmed with measurements. The method should also work well for higher Qs, and can be easily applied in RF power coupler designs and HOM damping for normal-conducting and superconducting cavities.

J. Shi; H. Chen; S. Zheng; D. Li; R.A. Rimmer; H. Wang

2006-06-26T23:59:59.000Z

87

A Hybrid Laser-driven E-beam Injector Using Photo-cathode Electron Gun and superconducting Cavity*  

E-Print Network [OSTI]

A Hybrid Laser-driven E-beam Injector Using Photo-cathode Electron Gun and superconducting Cavity as a continuing effort towards a high-brightness superconducting RF injector. Various species of photo and one (betasuperconducting cavities operating under 2 K is to be constructed

Geng, Rong-Li

88

Superconductivity for Electric Systems  

E-Print Network [OSTI]

1 Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period October 1, 2006, to December 31, 2006 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For U.S. Department of Energy Office of Electricity Delivery

89

Superconductivity for Electric Systems  

E-Print Network [OSTI]

Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period January 1, 2007 to March 31, 2007 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For: Department of Energy Office of Electricity Delivery

90

Superconductivity for Electric Systems  

E-Print Network [OSTI]

Superconductivity for Electric Systems Superconductivity Program Quarterly Progress Report For the Period April 1, 2007, to June 30, 2007 #12;2 Superconductivity Program Quarterly Progress Report Superconductivity Program Oak Ridge National Laboratory For: Department of Energy Office of Electricity Delivery

91

Superconducting Magnet Division  

E-Print Network [OSTI]

Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R Slotted Dipole Corrector Design · Slots are machined in an Al tube where superconducting wires are placed between superconducting and copper solenoid with superconducting solenoid at 6T · The desired field (>0

Ohta, Shigemi

92

Fiber Optic Based Thermometry System for Superconducting RF Cavities  

SciTech Connect (OSTI)

Thermometry is recognized as the best technique to identify and characterize losses in SRF cavities. The most widely used and reliable apparatus for temperature mapping at cryogenic temperatures is based on carbon resistors (RTDs). The use of this technology on multi-cell cavities is inconvenient due to the very large number of sensors required to obtain sufficient spatial resolution. Recent developments make feasible the use of multiplexible fiber optic sensors for highly distributed temperature measurements. However, sensitivity of multiplexible cryogenic temperature sensors was found extending only to 12K at best and thus was not sufficient for SRF cavity thermometry. During the course of the project the team of MicroXact, JLab and Virginia Tech developed and demonstrated the multiplexible fiber optic sensor with adequate response below 20K. The demonstrated temperature resolution is by at least a factor of 60 better than that of the best multiplexible fiber optic temperature sensors reported to date. The clear path toward at least 10times better temperature resolution is shown. The first to date temperature distribution measurements with ~2.5mm spatial resolution was done with fiber optic sensors at 2K to4K temperatures. The repeatability and accuracy of the sensors were verified only at 183K, but at this temperature both parameters significantly exceeded the state of the art. The results of this work are expected to find a wide range of applications, since the results are enabling the whole new testing capabilities, not accessible before.

Dr. Kochergin, Vladimir [Microxact Inc.] [Microxact Inc.

2013-05-06T23:59:59.000Z

93

QUENCHES IN LARGE SUPERCONDUCTING MAGNETS  

E-Print Network [OSTI]

QUENCHES IN LARGE SUPERCONDUCTING MAGNETS. P. H. Eberhard,Study of an Unprotected Superconducting Coil Going Normal,"Method for Testing Superconducting Magnets," LBL Physics

Eberhard, P.H.

2010-01-01T23:59:59.000Z

94

RF power generation  

E-Print Network [OSTI]

This paper reviews the main types of r.f. power amplifiers which are, or may be, used for particle accelerators. It covers solid-state devices, tetrodes, inductive output tubes, klystrons, magnetrons, and gyrotrons with power outputs greater than 10 kW c.w. or 100 kW pulsed at frequencies from 50 MHz to 30 GHz. Factors affecting the satisfactory operation of amplifiers include cooling, matching and protection circuits are discussed. The paper concludes with a summary of the state of the art for the different technologies.

Carter, R G

2011-01-01T23:59:59.000Z

95

A New First-Principles Calculation of Field-Dependent RF Surface Impedance of BCS Superconductor  

SciTech Connect (OSTI)

There is a need to understand the intrinsic limit of radiofrequency (RF) surface impedance that determines the performance of superconducting RF cavities in particle accelerators. Here we present a field-dependent derivation of Mattis-Bardeen theory of the RF surface impedance of BCS superconductors based on the shifted density of states resulting from coherently moving Cooper pairs. Our theoretical prediction of the effective BCS RF surface resistance (Rs) of niobium as a function of peak surface magnetic field amplitude agrees well with recently reported record low loss resonant cavity measurements from JLab and FNAL with carefully, yet differently, prepared niobium material. The surprising reduction in resistance with increasing field is explained to be an intrinsic effect.

Xiao, Binping [Brookhaven National Laboratory, Upton, New York (United States); Reece, Charles E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2014-02-01T23:59:59.000Z

96

Feedback Configuration Tools for LHC Low Level RF  

SciTech Connect (OSTI)

The LHC Low Level RF System (LLRF) is a complex multi-VME crate system which is used to regulate the superconductive cavity gap voltage as well as to lower the impedance as seen by the beam through low latency feedback. This system contains multiple loops with several parameters to be set before the loops can be closed. In this paper, we present a suite of MATLAB based tools developed to perform the preliminary alignment of the RF stations and the beginnings of a closed loop model based alignment routine. We briefly introduce the RF system and in particular the base band (time domain noise based) network analyzer system built into the LHC LLRF. The main focus of this paper is the methodology of the algorithms used by the routines within the context of the overall system. Measured results are presented that validate the technique. Because the RF systems are located in a cavern 120 m underground in a location which is relatively un-accessible without beam and completely un-accessible with beam present or magnets are energized, these remotely operated tools are a necessity for the CERN LLRF team to maintain and tune their LLRF systems in a similar fashion as to what was done very successfully in PEP-II at SLAC.

Van Winkle, D.; Fox, J.; Mastorides, T.; Rivetta, C.; /SLAC; Baudrenghien, P.; Butterworth, A.; Molendijk, J.; /CERN

2009-12-16T23:59:59.000Z

97

Superconducting cavity transducer for resonant gravitational radiation antennas  

E-Print Network [OSTI]

Parametric transducers, such as superconducting rf cavities, can boost the bandwidth and sensitivity of the next generation resonant antennas, thanks to a readily available technology. We have developed a fully coupled dynamic model of the system "antenna--transducer" and worked out some estimates of signal--to--noise ratio and the stability conditions in various experimental configurations. We also show the design and the prototype of a rf cavity which, together with a suitable read--out electronic, will be used as a test bench for the parametric transducer.

R. Ballantini; M. Bassan; A. Chincarini; G. Gemme; R. Parodi; R. Vaccarone

2006-02-15T23:59:59.000Z

98

Maximum screening fields of superconducting multilayer structures  

E-Print Network [OSTI]

It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields $H_s$ of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness $\\sim 0.1\\; \\mu$m at the Nb surface could increase $H_s\\simeq 240$ mT of a clean Nb up to $H_s\\simeq 290$ mT. Optimized multilayers of Nb$_3$Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.

Gurevich, Alex

2015-01-01T23:59:59.000Z

99

Improved nuclear magnetic resonance apparatus having semitoroidal rf coil for use in topical NMR and NMR imaging  

DOE Patents [OSTI]

An improved nuclear magnetic resonance (NMR) apparatus for use in topical magnetic resonance (TMR) spectroscopy and other remote sensing NMR applications includes a semitoroidal radio frequency (rf) coil. The semitoroidal rf coil produces an effective alternating magnetic field at a distance from the poles of the coil, so as to enable NMR measurements to be taken from selected regions inside an object, particularly including human and other living subjects. The semitoroidal rf coil is relatively insensitive to magnetic interference from metallic objects located behind the coil, thereby rendering the coil particularly suited for use in both conventional and superconducting NMR magnets. The semitoroidal NMR coil can be constructed so that it emits little or no excess rf electric field associated with the rf magnetic field, thus avoiding adverse effects due to dielectric heating of the sample or to any other interaction of the electric field with the sample.

Fukushima, E.; Roeder, S.B.W.; Assink, R.A.; Gibson, A.A.V.

1984-01-01T23:59:59.000Z

100

Response of radio frequency superconducting quantum interference devices to electromagnetic interference  

SciTech Connect (OSTI)

A number of applications of high-temperature superconductor radio frequency superconducting quantum interference devices (rf SQUIDs) require a certain immunity of these sensors against electromagnetic interference (EMI). We have investigated effects of electromagnetic radiation in the high-frequency and ultrahigh-frequency range on various types of rf SQUIDs. It has been found that EMI of sufficient field strength reduces the voltage versus flux transfer function, and thus increases the flux noise of the SQUIDs. SQUIDs with a wire wound tank circuit coil have been found to be more sensitive to EMI than SQUIDs integrated into a superconducting microstrip resonator. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Mueck, M.; Dechert, J.; Gail, J.; Kreutzbruck, M.; Schoene, S.; Weidl, R. [Institut fuer Angewandte Physik, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany)] [Institut fuer Angewandte Physik, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany)

1995-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Superconducting magnet  

DOE Patents [OSTI]

A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

Satti, John A. (Naperville, IL)

1980-01-01T23:59:59.000Z

102

Superconducting microfabricated ion traps  

E-Print Network [OSTI]

We fabricate superconducting ion traps with niobium and niobium nitride and trap single [superscript 88]Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the ...

Wang, Shannon Xuanyue

103

Basic principle of superconductivity  

E-Print Network [OSTI]

The basic principle of superconductivity is suggested in this paper. There have been two vital wrong suggestions on the basic principle, one is the relation between superconductivity and the Bose-Einstein condensation (BEC), and another is the relation between superconductivity and pseudogap.

Tian De Cao

2009-11-10T23:59:59.000Z

104

Superconducting Magnet Division  

E-Print Network [OSTI]

Superconducting Magnet Division Ramesh Gupta 20T Target Solenoid with HTS Insert Solenoid Capture Laboratory New York, USA http://www.bnl.gov/magnets/staff/gupta #12;Superconducting Magnet Division Ramesh of HTS may significantly reduce the amount of Tungsten shielding · Summary #12;Superconducting Magnet

McDonald, Kirk

105

Fast Ferroelectric L-Band Tuner for Superconducting Cavities  

SciTech Connect (OSTI)

Design, analysis, and low-power tests are described on a ferroelectric tuner concept that could be used for controlling external coupling to RF cavities for the superconducting Energy Recovery Linac (ERL) in the electron cooler of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). The tuner configuration utilizes several small donut-shaped ferroelectric assemblies, which allow the design to be simpler and more flexible, as compared to previous designs. Design parameters for 704 and 1300 MHz versions of the tuner are given. Simulation results point to efficient performance that could reduce by a factor-of-ten the RF power levels required for driving superconducting cavities in the BNL ERL.

Jay L. Hirshfield

2012-07-03T23:59:59.000Z

106

Protective link for superconducting coil  

DOE Patents [OSTI]

A superconducting coil system includes a superconducting coil and a protective link of superconducting material coupled to the superconducting coil. A rotating machine includes first and second coils and a protective link of superconducting material. The second coil is operable to rotate with respect to the first coil. One of the first and second coils is a superconducting coil. The protective link is coupled to the superconducting coil.

Umans, Stephen D. (Belmont, MA)

2009-12-08T23:59:59.000Z

107

Status of the plasma generator of the superconducting proton linac  

SciTech Connect (OSTI)

In the framework of the superconducting proton linac (SPL) study at CERN, a new non-cesiated H{sup -} plasma generator driven by an external 2 MHz RF antenna has been developed and successfully operated at repetition rates of 50 Hz, pulse lengths of up to 3 ms, and average RF powers of up to 3 kW. The coupling efficiency of RF power into the plasma was determined by the cooling water temperatures and the analysis of the RF forward and reflected power and the antenna current and amounts to 50%-60%. The plasma resistance increases between 10 kW and 40 kW RF power from about 0.45 {Omega} to 0.65 {Omega}. Measurements of RF power dissipated in the ferrites and the magnets on a test bench show a 5-fold decrease of the power losses for the magnets when they are contained in a Cu box, thus validating the strategy of shielding the magnets with a high electrical conductivity material. An air cooling system was installed in the SPL plasma generator to control the temperatures of the ferrites despite hysteresis losses of several Watts.

Kronberger, M.; Lettry, J.; Paoluzzi, M.; Pereira, H.; Arias, J. Sanchez; Schmitzer, C.; Scrivens, R. [European Organisation for Nuclear Research, CERN, 1211 Geneva 23 (Switzerland); Faircloth, D. [STFC, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom)

2012-02-15T23:59:59.000Z

108

Superconducting hot-electron nanobolometer with microwave bias and readout  

E-Print Network [OSTI]

We propose a new detection technique based on radio-frequency (RF) bias and readout of an antenna-coupled superconducting nanobolometer. This approach is suitable for Frequency-Division-Multiplexing (FDM) readout of large arrays using broadband low-noise RF amplifier. We call this new detector RFTES. This feasibility study was made on demonstrator devices which are made in all-Nb technology and operate at 4.2 K. The studied RFTES devices consist of an antenna-coupled superconducting nanobolometer made of ultrathin niobium films with transition temperature Tc = 5.2 K. The 0.65-THz antenna and nanobolometer are embedded as a load into a GHz-range coplanar niobium resonator (Tc = 8.9 K, Q = 4000). To heat the superconducting Nb nanobolometer close to the Tc, the RF power at resonator frequency f = 5.8 GHz is applied via a transmission line which is weakly coupled (-11 dB) to the loaded resonator. The THz-antenna of RFTES was placed in the focus of a sapphire immersion lens inside a He4-cryostat equipped with an ...

Kuzmin, A A; Shitov, S V; Abramov, N N; Ermakov, A B; Arndt, M; Wuensch, S H; Ilin, K S; Ustinov, A V; Siegel, M

2014-01-01T23:59:59.000Z

109

Unbalanced field RF electron gun  

DOE Patents [OSTI]

A design for an RF electron gun having a gun cavity utilizing an unbalanced electric field arrangement. Essentially, the electric field in the first (partial) cell has higher field strength than the electric field in the second (full) cell of the electron gun. The accompanying method discloses the use of the unbalanced field arrangement in the operation of an RF electron gun in order to accelerate an electron beam.

Hofler, Alicia

2013-11-12T23:59:59.000Z

110

Broadband sample holder for microwave spectroscopy of superconducting qubits  

SciTech Connect (OSTI)

We present a practical design and implementation of a broadband sample holder suitable for microwave experiments with superconducting integrated circuits at millikelvin temperatures. Proposed design can be easily integrated in standard dilution cryostats, has flat pass band response in a frequency range from 0 to 32 GHz, allowing the RF testing of the samples with substrate size up to 4 × 4 mm{sup 2}. The parasitic higher modes interference in the holder structure is analyzed and prevented via design considerations. The developed setup can be used for characterization of superconducting parametric amplifiers, bolometers, and qubits. We tested the designed sample holder by characterizing of a superconducting flux qubit at 20 mK temperature.

Averkin, A. S.; Karpov, A.; Glushkov, E.; Abramov, N. [National University of Science and Technology (MISIS), Leninskiy prosp. 4, Moscow, 119049 (Russian Federation); Shulga, K. [National University of Science and Technology (MISIS), Leninskiy prosp. 4, Moscow, 119049 (Russian Federation); Russian Quantum Center (RQC), 100 Novaya St., Skolkovo, Moscow region, 143025 (Russian Federation); Huebner, U. [Leibniz Institute of Photonic Technology (IPHT), PO Box 100239, D-07702 Jena (Germany); Il'ichev, E. [Russian Quantum Center (RQC), 100 Novaya St., Skolkovo, Moscow region, 143025 (Russian Federation); Leibniz Institute of Photonic Technology (IPHT), PO Box 100239, D-07702 Jena (Germany); Ustinov, A. V. [National University of Science and Technology (MISIS), Leninskiy prosp. 4, Moscow, 119049 (Russian Federation); Russian Quantum Center (RQC), 100 Novaya St., Skolkovo, Moscow region, 143025 (Russian Federation); Physikalisches Institut, Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe (Germany)

2014-10-15T23:59:59.000Z

111

Superconducting radiofrequency window assembly  

DOE Patents [OSTI]

The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly has a superconducting metal-ceramic design. The srf window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.

Phillips, H.L.; Elliott, T.S.

1997-03-11T23:59:59.000Z

112

Superconductive radiofrequency window assembly  

DOE Patents [OSTI]

The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The SRF window assembly has a superconducting metal-ceramic design. The SRF window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the SRF window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.

Phillips, H.L.; Elliott, T.S.

1998-05-19T23:59:59.000Z

113

Philosophy 26 High Temperature Superconductivity  

E-Print Network [OSTI]

Philosophy 26 High Temperature Superconductivity By Ohm's Law, resistance will dim. Low temperature superconductivity was discovered in 1911 by Heike was explained by BCS theory. BCS theory explains superconductivity microscopically

Callender, Craig

114

Engineering Division Superconducting  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

& Engineering Division Superconducting Magnet Technology for Fusion and Large Scale Applications Joseph V. Minervini Massachusetts Institute of Technology Plasma Science and Fusion...

115

Superconductive imaging surface magnetometer  

DOE Patents [OSTI]

An improved pick-up coil system for use with Superconducting Quantum Interference Device gradiometers and magnetometers involving the use of superconducting plates near conventional pick-up coil arrangements to provide imaging of nearby dipole sources and to deflect environmental magnetic noise away from the pick-up coils. This allows the practice of gradiometry and magnetometry in magnetically unshielded environments. One embodiment uses a hemispherically shaped superconducting plate with interior pick-up coils, allowing brain wave measurements to be made on human patients. another embodiment using flat superconducting plates could be used in non-destructive evaluation of materials.

Overton, Jr., William C. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM); Flynn, Edward R. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

116

Cryogenic vacuumm RF feedthrough device  

DOE Patents [OSTI]

A cryogenic vacuum rf feedthrough device comprising: 1) a probe for insertion into a particle beam; 2) a coaxial cable comprising an inner conductor and an outer conductor, a dielectric/insulating layer surrounding the inner conductor, the latter being connected to the probe for the transmission of higher mode rf energy from the probe; and 3) a high thermal conductivity stub attached to the coaxial dielectric about and in thermal contact with the inner conductor which high thermal conductivity stub transmits heat generated in the vicinity of the probe efficiently and radially from the area of the probe and inner conductor all while maintaining useful rf transmission line characteristics between the inner and outer coaxial conductors.

Wu, Genfa (Yorktown, VA); Phillips, Harry Lawrence (Hayes, VA)

2008-12-30T23:59:59.000Z

117

Note on RF Photo-Cathode Gun  

E-Print Network [OSTI]

Emittances in Laser-Driven RF Guns", Proc. 1988 Linear Acc.Palmer, "Preliminary Study of Gun Emittance Correction", BNLLaser-Driven RF Electron Guns", Nuc1. ln stt. Meth. , A275,

Kim, Kwang-Je

2010-01-01T23:59:59.000Z

118

Intelligent Radio Frequency (RF) Monitoring  

E-Print Network [OSTI]

? Intelligent Radio Frequency (RF) Monitoring ? 2009 Armstrong International, Inc. www.armstronginternational.com 2 ?Expect many enjoyable experiences!? David M. Armstrong Present Process Challenges ? Identifying a failure ? Procedure.... Armstrong Steam Trap Challenges ? Identifying a failure ? Manpower ? Location ? Magnitude of failure ? Energy loss ? Loss of heat transfer ? Justification for repair ? ?Speed of Implementation? ? Environmental concerns Manpower Location 4...

Kimbrough, B.

119

High-Power Rf Load  

DOE Patents [OSTI]

A compact high-power RF load comprises a series of very low Q resonators, or chokes [16], in a circular waveguide [10]. The sequence of chokes absorb the RF power gradually in a short distance while keeping the bandwidth relatively wide. A polarizer [12] at the input end of the load is provided to convert incoming TE.sub.10 mode signals to circularly polarized TE.sub.11 mode signals. Because the load operates in the circularly polarized mode, the energy is uniformly and efficiently absorbed and the load is more compact than a rectangular load. Using these techniques, a load having a bandwidth of 500 MHz can be produced with an average power dissipation level of 1.5 kW at X-band, and a peak power dissipation of 100 MW. The load can be made from common lossy materials, such as stainless steel, and is less than 15 cm in length. These techniques can also produce loads for use as an alternative to ordinary waveguide loads in small and medium RF accelerators, in radar systems, and in other microwave applications. The design is easily scalable to other RF frequencies and adaptable to the use of other lossy materials.

Tantawi, Sami G. (San Mateo, CA); Vlieks, Arnold E. (Livermore, CA)

1998-09-01T23:59:59.000Z

120

Josephson device with a matched rf source  

SciTech Connect (OSTI)

Analog simulation of a resistance-shunted ac Josephson junction coupled to an rf source with matching impedance reveals (1) added structure in the device's V-I curve even when the source is quiescent and (2) rf-induced steps with peak amplitudes between those produced by voltage and current rf sources. Both results are consistent with experimental data.

Longacre, A. Jr.

1980-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Superconducting Radiofrequency (SRF) Accelerator Cavities  

ScienceCinema (OSTI)

Charlie Reece, an accelerator technology scientist, explains how superconducting radiofrequency accelerator cavities work.

Reece, Charlie

2014-05-22T23:59:59.000Z

122

RF Design Optimization for New Injector Cryounit at CEBAF  

SciTech Connect (OSTI)

A new injector superconducting RF (SRF) cryounit with one new 2-cell, B=0.6 cavity plus one refurbished 7-cell, B=0.97, C100 style cavity has been re-designed and optimized for the engineering compatibility of existing module for CEBAF operation. The optimization of 2-cell cavity shape for longitudinal beam dynamic of acceleration from 200keV to 533keV and the minimization of transverse kick due to the waveguide couplers to less than 1 mrad have been considered. Operating at 1497MHz, two cavities has been designed into a same footprint of CEBAF original quarter cryomodule to deliver an injection beam energy of 5MeV in less than 0.27{degree} rms bunch length and a maximum energy spread of 5keV.

Wang, Haipeng; Cheng, Guangfeng; Hannon, Fay E.; Hofler, Alicia S.; Kazimi, Reza; Preble, Joe; Rimmer, Robert A.

2013-06-01T23:59:59.000Z

123

National RF Test Facility as a multipurpose development tool  

SciTech Connect (OSTI)

Additions and modifications to the National RF Test Facility design have been made that (1) focus its use for technology development for future large systems in the ion cyclotron range of frequencies (ICRF), (2) expand its applicability to technology development in the electron cyclotron range of frequencies (ECRF) at 60 GHz, (3) provide a facility for ELMO Bumpy Torus (EBT) 60-GHz ring physics studies, and (4) permit engineering studies of steady-state plasma systems, including superconducting magnet performance, vacuum vessel heat flux removal, and microwave protection. The facility will continue to function as a test bed for generic technology developments for ICRF and the lower hybrid range of frequencies (LHRF). The upgraded facility is also suitable for mirror halo physics experiments.

McManamy, T.J.; Becraft, W.R.; Berry, L.A.; Blue, C.W.; Gardner, W.L.; Haselton, H.H.; Hoffman, D.J.; Loring, C.M. Jr.; Moeller, F.A.; Ponte, N.S.

1983-01-01T23:59:59.000Z

124

Decrease of the surface resistance in superconducting niobium resonator cavities by the microwave field  

SciTech Connect (OSTI)

Measurements of the quality factor, Q, of Nb superconducting microwave resonators often show that Q increases by {approx_equal} 10%–30% with increasing radio-frequency (rf) field, H, up to {approx} 15-20 mT. Recent high temperature heat treatments can amplify this rf field-induced increase of Q up to {approx_equal} 50%–100% and extend it to much higher fields, but the mechanisms of the enhancement of Q(H) remain unclear. Here, we suggest a method to reveal these mechanisms by measuring temperature dependencies of Q at different rf field amplitudes. We show that the increase of Q(H) does not come from a field dependent quasi-particles activation energy or residual resistance, but rather results from the smearing of the density of state by the rf field.

Ciovati, Gianluigi [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Dhakal, Pashupati [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Gurevich, Alexander V. [Old Dominion University, Norfolk, VA (United States)

2014-03-01T23:59:59.000Z

125

Superconducting Magnet Technology for Future Hadron Colliders  

E-Print Network [OSTI]

I. Superconducting Magnet Technology for Future Hadl"On1994. M.N. Wilson, Superconducting Magnets (Clarendon Press,The application of superconducting magnets to large-scale

Scanlan, R.M.

2011-01-01T23:59:59.000Z

126

Superconducting vortex pinning with artificially prepared nanostructures  

E-Print Network [OSTI]

K. Schuller, “Enhanced superconducting vortex pinning withat T/Tc = 0.99 of a superconducting Nb thin film on aof the triangles. The superconducting critical temperature

Rosen, Yaniv Jacob

127

Fluctuations in systemsFluctuations in systems with superconducting islandswith superconducting islands  

E-Print Network [OSTI]

Fluctuations in systemsFluctuations in systems with superconducting islandswith superconductingTwo mechanism of TTcc suppressionsuppression #12;SuperconductingSuperconductingmetal transitionsmetal: Superconductive transitionGrains: Superconductive transition #12;Islands on a film: what's the difference

Fominov, Yakov

128

Introduction to Color Superconductivity  

E-Print Network [OSTI]

At high nuclear density and small temperature, due to the asymptotic freedom property of Quantum ChromoDynamics and to the existence of an attractive channel in the color interaction, diquark condensates might be formed. Since these condensates break the color gauge symmetry, this phenomenon has the name of color superconductivity. In the last few years this has become a very active field of research. While a direct experimental test is still missing, color superconductivity might have implications in astrophysics because for some compact stars, e.g. pulsars, the baryon densities necessary for color superconductivity can probably be reached.

G. Nardulli

2006-10-23T23:59:59.000Z

129

Superconducting active impedance converter  

DOE Patents [OSTI]

A transimpedance amplifier for use with high temperature superconducting, other superconducting, and conventional semiconductors allows for appropriate signal amplification and impedance matching to processing electronics. The amplifier incorporates the superconducting flux flow transistor into a differential amplifier configuration which allows for operation over a wide temperature range, and is characterized by high gain, relatively low noise, and response times less than 200 picoseconds over at least a 10-80 K. temperature range. The invention is particularly useful when a signal derived from either far-IR focal plane detectors or from Josephson junctions is to be processed by higher signal/higher impedance electronics, such as conventional semiconductor technology. 12 figures.

Ginley, D.S.; Hietala, V.M.; Martens, J.S.

1993-11-16T23:59:59.000Z

130

Superconducting active impedance converter  

DOE Patents [OSTI]

A transimpedance amplifier for use with high temperature superconducting, other superconducting, and conventional semiconductor allows for appropriate signal amplification and impedance matching to processing electronics. The amplifier incorporates the superconducting flux flow transistor into a differential amplifier configuration which allows for operation over a wide temperature range, and is characterized by high gain, relatively low noise, and response times less than 200 picoseconds over at least a 10-80 K. temperature range. The invention is particularly useful when a signal derived from either far-IR focal plane detectors or from Josephson junctions is to be processed by higher signal/higher impedance electronics, such as conventional semiconductor technology.

Ginley, David S. (Albuquerque, NM); Hietala, Vincent M. (Placitas, NM); Martens, Jon S. (Albuquerque, NM)

1993-01-01T23:59:59.000Z

131

Superconducting thermoelectric generator  

DOE Patents [OSTI]

An apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.

Metzger, J.D.; El-Genk, M.S.

1996-01-01T23:59:59.000Z

132

Superconducting thermoelectric generator  

DOE Patents [OSTI]

An apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.

Metzger, John D. (Eaton's Neck, NY); El-Genk, Mohamed S. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

133

Superconducting thermoelectric generator  

DOE Patents [OSTI]

An apparatus and method for producing electricity from heat is disclosed. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device. 4 figs.

Metzger, J.D.; El-Genk, M.S.

1998-05-05T23:59:59.000Z

134

Superconducting transmission line particle detector  

DOE Patents [OSTI]

A microvertex particle detector for use in a high energy physic collider including a plurality of parallel superconducting thin film strips separated from a superconducting ground plane by an insulating layer to form a plurality of superconducting waveguides. The microvertex particle detector indicates passage of a charged subatomic particle by measuring a voltage pulse measured across a superconducting waveguide caused by the transition of the superconducting thin film strip from a superconducting to a non- superconducting state in response to the passage of a charged particle. A plurality of superconducting thin film strips in two orthogonal planes plus the slow electromagnetic wave propagating in a superconducting transmission line are used to resolve N/sup 2/ ambiguity of charged particle events. 6 figs.

Gray, K.E.

1988-07-28T23:59:59.000Z

135

Superconducting transmission line particle detector  

DOE Patents [OSTI]

A microvertex particle detector for use in a high energy physic collider including a plurality of parallel superconducting thin film strips separated from a superconducting ground plane by an insulating layer to form a plurality of superconducting waveguides. The microvertex particle detector indicates passage of a charged subatomic particle by measuring a voltage pulse measured across a superconducting waveguide caused by the transition of the superconducting thin film strip from a superconducting to a non-superconducting state in response to the passage of a charged particle. A plurality of superconducting thin film strips in two orthogonal planes plus the slow electromagnetic wave propogating in a superconducting transmission line are used to resolve N.sup.2 ambiguity of charged particle events.

Gray, Kenneth E. (Naperville, IL)

1989-01-01T23:59:59.000Z

136

Low jitter RF distribution system  

DOE Patents [OSTI]

A timing signal distribution system includes an optical frequency stabilized laser signal amplitude modulated at an rf frequency. A transmitter box transmits a first portion of the laser signal and receive a modified optical signal, and outputs a second portion of the laser signal and a portion of the modified optical signal. A first optical fiber carries the first laser signal portion and the modified optical signal, and a second optical fiber carries the second portion of the laser signal and the returned modified optical signal. A receiver box receives the first laser signal portion, shifts the frequency of the first laser signal portion outputs the modified optical signal, and outputs an electrical signal on the basis of the laser signal. A detector at the end of the second optical fiber outputs a signal based on the modified optical signal. An optical delay sensing circuit outputs a data signal based on the detected modified optical signal. An rf phase detect and correct signal circuit outputs a signal corresponding to a phase stabilized rf signal based on the data signal and the frequency received from the receiver box.

Wilcox, Russell; Doolittle, Lawrence; Huang, Gang

2012-09-18T23:59:59.000Z

137

Progress in Superconducting Metamaterials  

E-Print Network [OSTI]

We review progress in the development and applications of superconducting metamaterials. The review is organized in terms of several distinct advantages and unique properties brought to the metamaterials field by superconductivity. These include the low-loss nature of the meta-atoms, their compact structure, their extraordinary degree of nonlinearity and tunability, magnetic flux quantization and the Josephson effect, quantum effects in which photons interact with quantized energy levels in the meta-atom, as well as strong diamagnetism.

Philipp Jung; Alexey V. Ustinov; Steven M. Anlage

2014-03-25T23:59:59.000Z

138

Superconductivity Conference Held  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystalline Gallium OxideSumin KimSuperconductingSuperconductivity

139

Superconducting radiofrequency window assembly  

DOE Patents [OSTI]

The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.

Phillips, Harry L. (Seaford, VA); Elliott, Thomas S. (Yorktown, VA)

1997-01-01T23:59:59.000Z

140

Superconductive radiofrequency window assembly  

DOE Patents [OSTI]

The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.

Phillips, Harry Lawrence (Seaford, VA); Elliott, Thomas S. (Yorktown, VA)

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

High temperature interfacial superconductivity  

DOE Patents [OSTI]

High-temperature superconductivity confined to nanometer-scale interfaces has been a long standing goal because of potential applications in electronic devices. The spontaneous formation of a superconducting interface in bilayers consisting of an insulator (La.sub.2CuO.sub.4) and a metal (La.sub.1-xSr.sub.xCuO.sub.4), neither of which is superconducting per se, is described. Depending upon the layering sequence of the bilayers, T.sub.c may be either .about.15 K or .about.30 K. This highly robust phenomenon is confined to within 2-3 nm around the interface. After exposing the bilayer to ozone, T.sub.c exceeds 50 K and this enhanced superconductivity is also shown to originate from a 1 to 2 unit cell thick interfacial layer. The results demonstrate that engineering artificial heterostructures provides a novel, unconventional way to fabricate stable, quasi two-dimensional high T.sub.c phases and to significantly enhance superconducting properties in other superconductors. The superconducting interface may be implemented, for example, in SIS tunnel junctions or a SuFET.

Bozovic, Ivan (Mount Sinai, NY); Logvenov, Gennady (Port Jefferson Station, NY); Gozar, Adrian Mihai (Port Jefferson, NY)

2012-06-19T23:59:59.000Z

142

Single electron beam rf feedback free electron laser  

DOE Patents [OSTI]

A free electron laser system and electron beam system for a free electron laser which uses rf feedback to enhance efficiency are described. Rf energy is extracted from a single electron beam by decelerating cavities and energy is returned to accelerating cavities using rf returns, such as rf waveguides, rf feedthroughs, resonant feedthroughs, etc. This rf energy is added to rf klystron energy to reduce the required input energy and thereby enhance energy efficiency of the system.

Brau, C.A.; Stein, W.E.; Rockwood, S.D.

1981-02-11T23:59:59.000Z

143

7 Superconductivity March 12, 2008  

E-Print Network [OSTI]

to measure. Current could be left flowing round a superconducting loop for several months without any and copper, do not seem to be superconducting, nor do the elements in Group IIA, such as calcium, but many

Thouless, David

144

Witten Index and Superconducting Strings  

E-Print Network [OSTI]

The Yukawa interaction sector of superstring inspired models that give superconducting strings, can be described in terms of a supersymmetric quantum mechanics algebra. We relate the Witten index of susy quantum mechanics with an index characteristic to superconducting string models.

V. K. Oikonomou

2010-01-14T23:59:59.000Z

145

RF/optical shared aperture for high availability wideband communication RF/FSO links  

DOE Patents [OSTI]

An RF/Optical shared aperture is capable of transmitting and receiving optical signals and RF signals simultaneously. This technology enables compact wide bandwidth communications systems with 100% availability in clear air turbulence, rain and fog. The functions of an optical telescope and an RF reflector antenna are combined into a single compact package by installing an RF feed at either of the focal points of a modified Gregorian telescope.

Ruggiero, Anthony J; Pao, Hsueh-yuan; Sargis, Paul

2014-04-29T23:59:59.000Z

146

Tests of an RF Dipole Crabbing Cavity for an Electron-Ion Collider  

SciTech Connect (OSTI)

On the scheme of developing a medium energy electron-ion collider (MEIC) at Jefferson Lab, we have designed a compact superconducting rf dipole cavity at 750 MHz to crab both electron and ion bunches and increase luminosities at the interaction points (IP) of the machine. Following the design optimization and characterization of the electromagnetic properties such as peak surface fields and shunt impedance, along with field nonuniformities, multipole components content, higher order modes (HOM) and multipacting, a prototype cavity was built by Niowave Inc. The 750 MHz prototype crab cavity has been tested at 4 K and is ready for re-testing at 4 K and 2 K at Jefferson Lab. In this paper we present the detailed results of the rf tests performed on the 750 MHz crab cavity prototype.

Castilla Loeza, Alejandro [ODU, JLAB; Delayen, Jean R. [ODU, JLAB

2013-12-01T23:59:59.000Z

147

Options for an 11 GeV RF Beam Separator for the Jefferson Lab CEBAF Upgrade  

SciTech Connect (OSTI)

The CEBAF accelerator at Jefferson Lab has had, since first demonstration in 1996, the ability to deliver a 5-pass electron beam to experimental halls (A, B, and C) simultaneously. This capability was provided by a set of three, room temperature 499 MHz rf separators in the 5th pass beamline. The separator was two-rod, TEM mode type resonator, which has a high shunt impedance. The maximum rf power to deflect the 6 GeV beams was about 3.4kW. The 12 GeV baseline design does not preserve the capability of separating the 5th pass, 11 GeV beam for the 3 existing halls. Several options for restoring this capability, including extension of the present room temperature system or a new superconducting design in combination with magnetic systems, are under investigation and are presented.

Jean Delayen, Michael Spata, Haipeng Wang

2009-05-01T23:59:59.000Z

148

RF Surface Impedance Characterization of Potential New Materials for SRF-based Accelerators  

SciTech Connect (OSTI)

In the development of new superconducting materials for possible use in SRF-based accelerators, it is useful to work with small candidate samples rather than complete resonant cavities. The recently commissioned Jefferson Lab RF Surface Impedance Characterization (SIC) system can presently characterize the central region of 50 mm diameter disk samples of various materials from 2 to 40 K exposed to RF magnetic fields up to 14 mT at 7.4 GHz. We report the recent measurement results of bulk Nb, thin film Nb on Cu and sapphire substrates, Nb{sub 3}Sn sample, and thin film MgB{sub 2} on sapphire substrate provided by colleagues at JLab and Temple University.

Xiao, Binping [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States) and College of William and Mary, Williamsburg, VA (United States); Eremeev, Grigory V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Reece, Charles E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Phillips, H. Lawrence [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Kelley, Michael J. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2012-09-01T23:59:59.000Z

149

Superconductivity and Magnetism: Materials Properties  

E-Print Network [OSTI]

.g. within high-Tc superconductivity, magnetic superconductors, MgB2, CMR materials, nanomagnetism and spin#12;#12;Superconductivity and Magnetism: Materials Properties and Developments #12;Copyright 2003 Risø National Laboratory Roskilde, Denmark ISBN 87-550-3244-3 ISSN 0907-0079 #12;Superconductivity

150

Superconducting Magnet Division Mike Harrison  

E-Print Network [OSTI]

Superconducting Magnet Division Mike Harrison The LARP Dipole R&D Program - D1 only Design (high beta lattice location) · Beam heating (first active element from the IP) #12;Superconducting aperture Field quality Issues not (well ?) understood #12;Superconducting Magnet Division Mike Harrison

Large Hadron Collider Program

151

Interplay of superconductivity, magnetism, and density waves in rare-earth tritellurides and iron-based superconducting materials  

E-Print Network [OSTI]

B. Superconductivity . . . . . . . . . . . . . . . . .IV Superconductivity and Magnetism in Iron-PnictideSearch for Pressure Induced Superconductivity in Undoped Ce-

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

152

Orbit Spaces in Superconductivity  

E-Print Network [OSTI]

In the framework of Landau theory of phase transitions one is interested to describe all the possible low symmetry ``superconducting'' phases allowed for a given superconductor crystal and to determine the conditions under which this crystal undergoes a phase transition. These problems are best described and analyzed in the orbit space of the high symmetry group of the ``normal, non-superconducting'' phase of the crystal. In this article it is worked out a simple example concerning superconductivity, that shows the P-matrix method to determine the equations and inequalities defining the orbit space and its stratification. This approach is of general validity and can be used in all physical problems that make use of invariant functions, as long as the symmetry group is compact.

Vittorino Talamini

2006-07-30T23:59:59.000Z

153

Large Superconducting Magnet Systems  

E-Print Network [OSTI]

The increase of energy in accelerators over the past decades has led to the design of superconducting magnets for both accelerators and the associated detectors. The use of Nb?Ti superconducting materials allows an increase in the dipole field by up to 10 T compared with the maximum field of 2 T in a conventional magnet. The field bending of the particles in the detectors and generated by the magnets can also be increased. New materials, such as Nb3Sn and high temperature superconductor (HTS) conductors, can open the way to higher fields, in the range 13–20 T. The latest generations of fusion machines producing hot plasma also use large superconducting magnet systems.

Védrine, P

2014-01-01T23:59:59.000Z

154

Supertubes versus superconducting tubes  

E-Print Network [OSTI]

In this paper we show the relationship between cylindrical D2-branes and cylindrical superconducting membranes described by a generic effective action at the bosonic level. In the first case the extended objects considered, arose as blown up type IIA superstrings to D2-branes, named supertubes. In the second one, the cosmological objects arose from some sort of field theories. The Dirac-Born-Infeld action describing supertubes is shown to be equivalent to the generic effective action describing superconducting membranes via a special transformation.

Ruben Cordero; Efrain Rojas

2005-05-13T23:59:59.000Z

155

Superconducting Topological Insulators  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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156

SUPERCONDUCTIVITY PROGRAM RESEARCH AND DEVELOPMENT High Temperature Superconductivity (HTS) is a technology with the potential  

E-Print Network [OSTI]

#12;SUPERCONDUCTIVITY PROGRAM RESEARCH AND DEVELOPMENT High Temperature Superconductivity (HTS-of-way. The Department of Energy's efforts to advance High Temperature Superconductivity combine major national strengths: the Superconductivity Partnership Initiative (SPI), the 2nd Generation Wire Initiative

157

Robust Diamond-Based RF Switch Yields Enhanced Communication...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Robust Diamond-Based RF Switch Yields Enhanced Communication Capabilities Technology available for licesning: A radio frequency (RF) microelectromechanical system (MEMS) switch...

158

Superconducting Magnet Division  

E-Print Network [OSTI]

in the 400 kW end of RIA's Fragment Separator are subjected to several orders of magnitude more radiation an order of magnitude as compared to that for present superconducting accelerator magnets. An OPERA3d model://www.phy.anl.gov/ria/ http://www.orau.org/ria/ Figure: On this chart of the nuclides, black squares represent stable nuclei

Gupta, Ramesh

159

Superconducting thermoelectric generator  

DOE Patents [OSTI]

Thermoelectricity is produced by applying a temperature differential to dissimilar electrically conducting or semiconducting materials, thereby producing a voltage that is proportional to the temperature difference. Thermoelectric generators use this effect to directly convert heat into electricity; however, presently-known generators have low efficiencies due to the production of high currents which in turn cause large resistive heating losses. Some thermoelectric generators operate at efficiencies between 4% and 7% in the 800{degrees} to 1200{degrees}C range. According to its major aspects and bradly stated, the present invention is an apparatus and method for producing electricity from heat. In particular, the invention is a thermoelectric generator that juxtaposes a superconducting material and a semiconducting material - so that the superconducting and the semiconducting materials touch - to convert heat energy into electrical energy without resistive losses in the temperature range below the critical temperature of the superconducting material. Preferably, an array of superconducting material is encased in one of several possible configurations within a second material having a high thermal conductivity, preferably a semiconductor, to form a thermoelectric generator.

Metzger, J.D.; El-Genk, M.S.

1994-01-01T23:59:59.000Z

160

Langmuir vacuum and superconductivity  

SciTech Connect (OSTI)

It is shown that, in the 'jelly' model of cold electron-ion plasma, the interaction between electrons and the quantum electromagnetic vacuum of Langmuir waves involves plasma superconductivity with an energy gap proportional to the energy of the Langmuir quantum.

Veklenko, B. A. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

2012-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Higher Order Mode Heating Analysis for the ILC Superconducting Linacs  

SciTech Connect (OSTI)

The superconducting cavities and interconnects in the 11 km long linacs of the International Linear Collider (ILC) are designed to operate at 2K, where cooling costs are very expensive. It is thus important to minimize cryogenic heat loads. In addition to an unavoidable static load and the dynamic load of the fundamental 1.3 GHz accelerating rf, a further heat source is presented by the higher order mode (HOM) power deposited by the beam. Such modes will be damped by specially designed HOM couplers attached to the cavities (for trapped modes), and by ceramic dampers at 70K that are located between the eight or nine cavity cryomodules (for propagating modes). Brute force calculation of the higher frequency modes excited in a string of cryomodules is limited by computing capacity (see, e.g. [1]). M. Liepe has calculated {approx} 400 longitudinal TM modes in 3 superconducting cavities plus absorbers, up to 8 GHz [2]. Joestingmeier, et al., have used a ray tracing calculation to find the effect at higher frequencies, specifically in the range of tens of GHz and above [3]. In this report we present a scattering matrix approach, which we apply to an rf unit comprising 26 cavities and 3 absorbers. We perform calculations at sample frequencies (up to 20 GHz) to predict the effectiveness of the ceramic dampers in limiting HOM heat deposition at 2K.

Bane, K.L.F.; Nantista, C.; Adolphsen, C.; /SLAC; ,

2010-10-27T23:59:59.000Z

162

Cryogenic Test of a Coaxial Coupling Scheme for Fundamental and Higher Order Modes in Superconducting Cavities  

SciTech Connect (OSTI)

A coaxial coupling device located in the beam pipe of the TESLA type superconducting cavities provides for better propagation of Higher Order Modes (HOMs) and their strong damping in appropriate HOM couplers. Additionally, it also provides efficient coupling for fundamental mode RF power into the superconducting cavity. The whole coupling device can be designed as a detachable system. If appropriately dimensioned, the magnetic field can be minimized to a negligible level at the flange position. This scheme, presented previously*, provides for several advantages: strong HOM damping, flangeable solution, exchangeability of the HOM damping device on a cavity, less complexity of the superconducting cavity, possible cost advantages. This contribution will describe the results of the first cryogenic test.

J.K. Sekutowicz, P. Kneisel

2009-05-01T23:59:59.000Z

163

Matching network for RF plasma source  

DOE Patents [OSTI]

A compact matching network couples an RF power supply to an RF antenna in a plasma generator. The simple and compact impedance matching network matches the plasma load to the impedance of a coaxial transmission line and the output impedance of an RF amplifier at radio frequencies. The matching network is formed of a resonantly tuned circuit formed of a variable capacitor and an inductor in a series resonance configuration, and a ferrite core transformer coupled to the resonantly tuned circuit. This matching network is compact enough to fit in existing compact focused ion beam systems.

Pickard, Daniel S. (Palo Alto, CA); Leung, Ka-Ngo (Hercules, CA)

2007-11-20T23:59:59.000Z

164

THE Low-level Radio Frequency System for the superconducting cavities of National Synchrotron Light Source II  

SciTech Connect (OSTI)

A digital low-level radio frequency (LLRF) field controller has been developed for the storage ring of The National Synchrotron Light Source-II (NSLS-II). The primary performance goal for the LLRF is to support the required RF operation of the superconducting cavities with a beam current of 500mA and a 0.14 degree or better RF phase stability. The digital field controller is FPGA-based, in a standard format 19-inch/I-U chassis. It has an option of high-level control support with MATLAB running on a local host computer through a USB2.0 port. The field controller has been field tested with the high-power superconducting RF (SRF) at Canadian light Source, and successfully stored a high beam current of 250 mA. The test results show that required specifications for the cavity RF field stability are met. This digital field controller is also currently being used as a development platform for other functional modules in the NSLS-II RF systems.

Ma, H.; Rose, J.; Holub, B.; Cupolo, J.; Oliva, J.; Sikora, R.; Yeddulla, M.

2011-03-28T23:59:59.000Z

165

Superconducting vortex pinning with artificially prepared nanostructures  

E-Print Network [OSTI]

E. Dubin, Physica C: Superconductivity 369, 21 (2002). R. D.P. G. De Gennes, Superconductivity of Metals and Alloys (W.Schuller, Journal of Superconductivity and Novel Magnetism

Rosen, Yaniv Jacob

166

Superconductivity: the Gift that Keeps on Giving  

E-Print Network [OSTI]

Superconductivity: the Gift that Keeps on Giving Superconductivity, first discovered recently the discovery of high superconducting transition temperatures in the ceramic copper oxides has superconductors. In the underdoped or pseudogap phase of the cuprate superconductors, a significant portion

Goldberg, Bennett

167

Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara  

E-Print Network [OSTI]

Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara Department of Physics, University to the distinction between normal metals and insulators: the superconducting ``metal'' with delocalized qua- siparticle excitations and the superconducting ``insulator'' with localized quasiparticles. We describe

168

Superconducting solenoids for the Muon collider  

E-Print Network [OSTI]

muon collider has superconducting solenoids as an integralLBNL-44303 SCMAG-690 Superconducting Solenoids for the MuonDE-AC03-76SFOOO98. J Superconducting Solenoids for the Muon

Green, M.A.

2011-01-01T23:59:59.000Z

169

SUPERCONDUCTING SHIELDING By W. O. HAMILTON,  

E-Print Network [OSTI]

41. SUPERCONDUCTING SHIELDING By W. O. HAMILTON, Stanford University, Department of Physics, Stanford, California (U.S.A.). Abstract. 2014 Superconducting shields offer the possibility of obtaining shielding from external time varying fields. Various techniques of superconducting shielding

Paris-Sud XI, Université de

170

HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network [OSTI]

D. C. 'Niobium-Titanium Superconducting Material s ', in S.14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.SUMAG-68 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS* C.

Taylor, C.

2011-01-01T23:59:59.000Z

171

Landscape of superconducting membranes  

E-Print Network [OSTI]

The AdS/CFT correspondence may connect the landscape of string vacua and the `atomic landscape' of condensed matter physics. We study the stability of a landscape of IR fixed points of N=2 large N gauge theories in 2+1 dimensions, dual to Sasaki-Einstein compactifications of M theory, towards a superconducting state. By exhibiting instabilities of charged black holes in these compactifications, we show that many of these theories have charged operators that condense when the theory is placed at a finite chemical potential. We compute a statistical distribution of critical superconducting temperatures for a subset of these theories. With a chemical potential of one milliVolt, we find critical temperatures ranging between 0.24 and 165 degrees Kelvin.

Frederik Denef; Sean A. Hartnoll

2009-03-20T23:59:59.000Z

172

Superconducting magnet wire  

DOE Patents [OSTI]

A superconducting tape or wire with an improved critical field is formed of alternating layers of a niobium-containing superconductor such as Nb, NbTi, Nb.sub.3 Sn or Nb.sub.3 Ge with a thickness in the range of about 0.5-1.5 times its coherence length, supported and separated by layers of copper with each copper layer having a thickness in the range of about 170-600 .ANG..

Schuller, Ivan K. (Woodridge, IL); Ketterson, John B. (Evanston, IL); Banerjee, Indrajit (San Jose, CA)

1986-01-01T23:59:59.000Z

173

Equilibrium Distributions and Superconductivity  

E-Print Network [OSTI]

In this article two models for charges distributions are discussed. On the basis of our consideration we put different points of view for stationary state. We prove that only finite energy model for charges' distribution and well-known variation principle explain some well-known experimental results. A new model for superconductivity was suggested, too. In frame of that model some characteristic experimental results for superconductors is possible to explain.

Ashot Vagharshakyan

2011-06-07T23:59:59.000Z

174

Helical superconducting black holes  

E-Print Network [OSTI]

We construct novel static, asymptotically $AdS_5$ black hole solutions with Bianchi VII$_0$ symmetry that are holographically dual to superconducting phases in four spacetime dimensions with a helical p-wave order. We calculate the precise temperature dependence of the pitch of the helical order. At zero temperature the black holes have vanishing entropy and approach domain wall solutions that reveal homogenous, non-isotropic dual ground states with emergent scaling symmetry.

Aristomenis Donos; Jerome P. Gauntlett

2012-05-17T23:59:59.000Z

175

Superconducting Topological Insulators  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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176

Superconductivity Centennial | Jefferson Lab  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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177

Competition between singlet and triplet superconductivity  

E-Print Network [OSTI]

The competition between singlet and triplet superconductivity is examined in consideration of correlations on an extended Hubbard model. It is shown that the triplet superconductivity may not be included in the common Hubbard model since the strong correlation favors the singlet superconductivity, and thus the triplet superconductivity should be induced by the electron-phonon interaction and the ferromagnetic exchange interaction. We also present a superconducting qualification with which magnetism is unbeneficial to superconductivity.

Tian De Cao; Tie Bang Wang

2009-10-04T23:59:59.000Z

178

Samsung: ENERGY STAR Referral (RF26VAB)  

Broader source: Energy.gov [DOE]

DOE referred the matter of Samsung refrigerator-freezer model RF26VAB to the EPA for appropriate action after DOE testing showed that the model does not meet the ENERGY STAR specification.

179

Si-based RF MEMS components.  

SciTech Connect (OSTI)

Radio frequency microelectromechanical systems (RF MEMS) are an enabling technology for next-generation communications and radar systems in both military and commercial sectors. RF MEMS-based reconfigurable circuits outperform solid-state circuits in terms of insertion loss, linearity, and static power consumption and are advantageous in applications where high signal power and nanosecond switching speeds are not required. We have demonstrated a number of RF MEMS switches on high-resistivity silicon (high-R Si) that were fabricated by leveraging the volume manufacturing processes available in the Microelectronics Development Laboratory (MDL), a Class-1, radiation-hardened CMOS manufacturing facility. We describe novel tungsten and aluminum-based processes, and present results of switches developed in each of these processes. Series and shunt ohmic switches and shunt capacitive switches were successfully demonstrated. The implications of fabricating on high-R Si and suggested future directions for developing low-loss RF MEMS-based circuits are also discussed.

Stevens, James E.; Nordquist, Christopher Daniel; Baker, Michael Sean; Fleming, James Grant; Stewart, Harold D.; Dyck, Christopher William

2005-01-01T23:59:59.000Z

180

Deeply scaled CMOS for RF power applications  

E-Print Network [OSTI]

The microelectronics industry is striving to reduce the cost, complexity, and form factor of wireless systems through single-chip integration of analog, RF and digital functions. Driven by the requirements of the digital ...

Scholvin, Jörg, 1976-

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Superconducting dark energy  

E-Print Network [OSTI]

Based on the analogy with superconductor physics we consider a scalar-vector-tensor gravitational model, in which the dark energy action is described by a gauge invariant electromagnetic type functional. By assuming that the ground state of the dark energy is in a form of a condensate with the U(1) symmetry spontaneously broken, the gauge invariant electromagnetic dark energy can be described in terms of the combination of a vector and of a scalar field (corresponding to the Goldstone boson), respectively. The gravitational field equations are obtained by also assuming the possibility of a non-minimal coupling between the cosmological mass current and the superconducting dark energy. The cosmological implications of the dark energy model are investigated for a Friedmann-Robertson-Walker homogeneous and isotropic geometry for two particular choices of the electromagnetic type potential, corresponding to a pure electric type field, and to a pure magnetic field, respectively. The time evolution of the scale factor, matter energy density and deceleration parameter are obtained for both cases, and it is shown that in the presence of the superconducting dark energy the Universe ends its evolution in an exponentially accelerating vacuum de Sitter state. By using the formalism of the irreversible thermodynamic processes for open systems we interpret the generalized conservation equations in the superconducting dark energy model as describing matter creation. The particle production rates, the creation pressure and the entropy evolution are explicitly obtained.

Shi-Dong Liang; Tiberiu Harko

2015-04-10T23:59:59.000Z

182

Superconductivity and Superfluidity  

E-Print Network [OSTI]

Currently there is a common belief that the explanation of superconductivity phenomenon lies in understanding the mechanism of the formation of electron pairs. Paired electrons, however, cannot form a superconducting condensate spontaneously. These paired electrons perform disorderly zero-point oscillations and there are no force of attraction in their ensemble. In order to create a unified ensemble of particles, the pairs must order their zero-point fluctuations so that an attraction between the particles appears. As a result of this ordering of zero-point oscillations in the electron gas, superconductivity arises. This model of condensation of zero-point oscillations creates the possibility of being able to obtain estimates for the critical parameters of elementary superconductors, which are in satisfactory agreement with the measured data. On the another hand, the phenomenon of superfluidity in He-4 and He-3 can be similarly explained, due to the ordering of zero-point fluctuations. It is therefore established that both related phenomena are based on the same physical mechanism.

B. V. Vasiliev

2013-10-31T23:59:59.000Z

183

Flavor Superconductivity & Superfluidity  

E-Print Network [OSTI]

In these lecture notes we derive a generic holographic string theory realization of a p-wave superconductor and superfluid. For this purpose we also review basic D-brane physics, gauge/gravity methods at finite temperature, key concepts of superconductivity and recent progress in distinct realizations of holographic superconductors and superfluids. Then we focus on a D3/D7-brane construction yielding a superconducting or superfluid vector-condensate. The corresponding gauge theory is 3+1-dimensional N=2 supersymmetric Yang-Mills theory with SU(N) color and SU(2) flavor symmetry. It shows a second order phase transition to a phase in which a U(1) subgroup of the SU(2) symmetry is spontaneously broken and typical superconductivity signatures emerge, such as a conductivity (pseudo-)gap and the Meissner-Ochsenfeld effect. Condensates of this nature are comparable to those recently found experimentally in p-wave superconductors such as a ruthenate compound. A string picture of the pairing mechanism and condensation is given using the exact knowledge of the corresponding field theory degrees of freedom.

Matthias Kaminski

2010-02-25T23:59:59.000Z

184

Superconducting VAR control. [Patent application  

DOE Patents [OSTI]

Static VAR control means are described employing an asymmetrically controlled Graetz bridge and a superconducting direct current coil having low losses and low cost characteristics.

Boenig, H.J.; Hassenzahl, W.V.

1980-12-05T23:59:59.000Z

185

EXPERIMENTAL STUDIES OF RF BREAKDOWNS IN THE COUPLER OF THE TTF RF GUN  

E-Print Network [OSTI]

to han- dle 800 µs long RF pulses with 4.5 MW of peak power and at 10 Hz repetition rate. In this regime

186

High-Temperature Superconducting Composite Conductors  

DOE Patents [OSTI]

Copper or excess copper is added to one or more layers of a superconducting composite structure to reduce migration of copper form a copper based superconducting layer.

Holesinger, Terry G. (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM); Arendt, Paul N. (Los Alamos, NM); Groves, James R. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Ayala, Alicia (Santa Fe, NM)

2005-01-18T23:59:59.000Z

187

Optimizing RF gun cavity geometry within an automated injector design system  

SciTech Connect (OSTI)

RF guns play an integral role in the success of several light sources around the world, and properly designed and optimized cw superconducting RF (SRF) guns can provide a path to higher average brightness. As the need for these guns grows, it is important to have automated optimization software tools that vary the geometry of the gun cavity as part of the injector design process. This will allow designers to improve existing designs for present installations, extend the utility of these guns to other applications, and develop new designs. An evolutionary algorithm (EA) based system can provide this capability because EAs can search in parallel a large parameter space (often non-linear) and in a relatively short time identify promising regions of the space for more careful consideration. The injector designer can then evaluate more cavity design parameters during the injector optimization process against the beam performance requirements of the injector. This paper will describe an extension to the APISA software that allows the cavity geometry to be modified as part of the injector optimization and provide examples of its application to existing RF and SRF gun designs.

Alicia Hofler ,Pavel Evtushenko

2011-03-28T23:59:59.000Z

188

Optimization of superconducting tiling pattern for superconducting bearings  

DOE Patents [OSTI]

An apparatus and method for reducing magnetic field inhomogeneities which produce rotational loss mechanisms in high temperature superconducting magnetic bearings are disclosed. Magnetic field inhomogeneities are reduced by dividing high temperature superconducting structures into smaller structures, and arranging the smaller structures into tiers which stagger the magnetic field maximum locations of the smaller structures. 20 figs.

Hull, J.R.

1996-09-17T23:59:59.000Z

189

Optimization of superconducting tiling pattern for superconducting bearings  

DOE Patents [OSTI]

An apparatus and method for reducing magnetic field inhomogeneities which produce rotational loss mechanisms in high temperature superconducting magnetic bearings. Magnetic field inhomogeneities are reduced by dividing high temperature superconducting structures into smaller structures, and arranging the smaller structures into tiers which stagger the magnetic field maximum locations of the smaller structures.

Hull, John R. (Hinsdale, IL)

1996-01-01T23:59:59.000Z

190

Power superconducting power transmission cable  

DOE Patents [OSTI]

The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

Ashworth, Stephen P. (Cambridge, GB)

2003-01-01T23:59:59.000Z

191

High critical current superconducting tapes  

DOE Patents [OSTI]

Improvements in critical current capacity for superconducting film structures are disclosed and include the use of a superconducting RE-BCO layer including a mixture of rare earth metals, e.g., yttrium and europium, where the ratio of yttrium to europium in the RE-BCO layer ranges from about 3 to 1 to from about 1.5 to 1.

Holesinger, Terry G. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

2003-09-23T23:59:59.000Z

192

Superconducting Topological Insulators  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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193

Superconducting Topological Insulators  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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194

2003 Annual Superconductivity2003 Annual Superconductivity Peer ReviewPeer Review  

E-Print Network [OSTI]

2003 Annual Superconductivity2003 Annual Superconductivity Peer ReviewPeer Review Raghu;Superconductivity Program at NREL for Electric SystemsSuperconductivity Program at NREL for Electric Systems Non) Industry CRADA:Industry CRADA: Oxford Superconducting Technologies (Ken Marken, Miao Hanping) *University

195

RF BREAKDOWN STUDIES USING PRESSURIZED CAVITIES  

SciTech Connect (OSTI)

Many present and future particle accelerators are limited by the maximum electric gradient and peak surface fields that can be realized in RF cavities. Despite considerable effort, a comprehensive theory of RF breakdown has not been achieved and mitigation techniques to improve practical maximum accelerating gradients have had only limited success. Part of the problem is that RF breakdown in an evacuated cavity involves a complex mixture of effects, which include the geometry, metallurgy, and surface preparation of the accelerating structures and the make-up and pressure of the residual gas in which plasmas form. Studies showed that high gradients can be achieved quickly in 805 MHz RF cavities pressurized with dense hydrogen gas, as needed for muon cooling channels, without the need for long conditioning times, even in the presence of strong external magnetic fields. This positive result was expected because the dense gas can practically eliminate dark currents and multipacting. In this project we used this high pressure technique to suppress effects of residual vacuum and geometry that are found in evacuated cavities in order to isolate and study the role of the metallic surfaces in RF cavity breakdown as a function of magnetic field, frequency, and surface preparation. One of the interesting and useful outcomes of this project was the unanticipated collaborations with LANL and Fermilab that led to new insights as to the operation of evacuated normal-conducting RF cavities in high external magnetic fields. Other accomplishments included: (1) RF breakdown experiments to test the effects of SF6 dopant in H2 and He gases with Sn, Al, and Cu electrodes were carried out in an 805 MHz cavity and compared to calculations and computer simulations. The heavy corrosion caused by the SF6 components led to the suggestion that a small admixture of oxygen, instead of SF6, to the hydrogen would allow the same advantages without the corrosion in a practical muon beam line. (2) A 1.3 GHz RF test cell capable of operating both at high pressure and in vacuum with replaceable electrodes was designed, built, and power tested in preparation for testing the frequency and geometry effects of RF breakdown at Argonne National Lab. At the time of this report this cavity is still waiting for the 1.3 GHz klystron to be available at the Wakefield Test Facility. (3) Under a contract with Los Alamos National Lab, an 805 MHz RF test cavity, known as the All-Seasons Cavity (ASC), was designed and built by Muons, Inc. to operate either at high pressure or under vacuum. The LANL project to use the (ASC) was cancelled and the testing of the cavity has been continued under the grant reported on here using the Fermilab Mucool Test Area (MTA). The ASC is a true pillbox cavity that has performed under vacuum in high external magnetic field better than any other and has demonstrated that the high required accelerating gradients for many muon cooling beam line designs are possible. (4) Under ongoing support from the Muon Acceleration Program, microscopic surface analysis and computer simulations have been used to develop models of RF breakdown that apply to both pressurized and vacuum cavities. The understanding of RF breakdown will lead to better designs of RF cavities for many applications. An increase in the operating accelerating gradient, improved reliability and shorter conditioning times can generate very significant cost savings in many accelerator projects.

Johnson, Rolland

2014-09-21T23:59:59.000Z

196

Wideband high efficiency CMOS envelope amplifiers for 4G LTE handset envelope tracking RF power amplifiers  

E-Print Network [OSTI]

RF power amplifier applications," IEEE Journal of Solid-RF power amplifier applications," IEEE Journal of Solid-RF power amplifier applications," IEEE Journal of Solid-

Hassan, Muhammad

2012-01-01T23:59:59.000Z

197

X-Band RF Gun Development  

SciTech Connect (OSTI)

In support of the MEGa-ray program at LLNL and the High Gradient research program at SLAC, a new X-band multi-cell RF gun is being developed. This gun, similar to earlier guns developed at SLAC for Compton X-ray source program, will be a standing wave structure made of 5.5 cells operating in the pi mode with copper cathode. This gun was designed following criteria used to build SLAC X-band high gradient accelerating structures. It is anticipated that this gun will operate with surface electric fields on the cathode of 200 MeV/m with low breakdown rate. RF will be coupled into the structure through a final cell with symmetric duel feeds and with a shape optimized to minimize quadrupole field components. In addition, geometry changes to the original gun, operated with Compton X-ray source, will include a wider RF mode separation, reduced surface electric and magnetic fields.

Vlieks, Arnold; Dolgashev, Valery; Tantawi, Sami; /SLAC; Anderson, Scott; Hartemann, Fred; Marsh, Roark; /LLNL, Livermore

2012-06-22T23:59:59.000Z

198

Quantum State Protection and Transfer Using Superconducting Qubits  

E-Print Network [OSTI]

relaxation . . . . . . . . .1.5 Superconducting ? ux-biasedCorrection Algorithms for Superconducting Qubits,” APS Marchand correction for superconducting qubits,” Phys. Rev. A,

Keane, Kyle Michael

2012-01-01T23:59:59.000Z

199

SUPERCONDUCTING TRANSITION EDGE BOLOMETER AND NOISE IN THIN FILMS  

E-Print Network [OSTI]

a) Composite Al superconducting bolometer (b) Composite SNSLBL-8019 SUPERCONDUCTING TRANSITION EDGE BOLOMETER AND INrights . LBL-8019 SUPERCONDUCTING TRANSITION EDGE BOLOMETER

Yeh, Nan-Hsiung

2011-01-01T23:59:59.000Z

200

Special issue on quantum computing with superconducting qubits  

E-Print Network [OSTI]

on quantum computing with superconducting qubits 10. Shaw,quantum computing with superconducting qubits Alexander N.years ago the ?rst superconducting qubit was demonstrated

Korotkov, Alexander N.

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

FORCED TWO PHASE HELIUM COOLING OF LARGE SUPERCONDUCTING MAGNETS  

E-Print Network [OSTI]

DIAMETER TPC THIN SUPERCONDUCTING SOLENOID . 'i.A. Green,and Construction of a Superconducting Stabilized AluminumM.A. Green, "Large Superconducting Detector Magnets with

Green, M.A.

2010-01-01T23:59:59.000Z

202

Exotic superconducting phases of ultracold atom mixtures on triangular lattices  

E-Print Network [OSTI]

Exotic Superconducting Phases of Ultracold Atom Mixtures onlattice contain exotic superconducting phases. For spin-1/2competition between superconducting phases with di?erent

Mathey, Ludwig; Tsai, Shan-Wen; Castro Neto, Antonio H.

2007-01-01T23:59:59.000Z

203

GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL  

E-Print Network [OSTI]

FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Thefailure of the first superconducting coil at the Lawrence

Green, M.A.

2010-01-01T23:59:59.000Z

204

A Superconducting transformer system for high current cable testing  

E-Print Network [OSTI]

A Superconducting Transformer System for High Current Cablea Direct-Current (DC) superconducting transformer system forhigh current test of superconducting cables. The transformer

Godeke, A.

2010-01-01T23:59:59.000Z

205

Progress on Superconducting Magnets for the MICE Cooling Channel  

E-Print Network [OSTI]

274 Progress on the Superconducting Magnets for the MICEM. A Green and J. M. Rey, “Superconducting Solenoids for anG, “Supercritically Cooled Superconducting Muon Channel,”

Green, Michael A

2010-01-01T23:59:59.000Z

206

CFN | Nanofabrication Group  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

CFN Operations Safety Awareness (COSA) form for cleanroom Cleanroom OrientationProtocols Electronic Chemical RecipeWaste Log instructions Request form for off-hours access (first...

207

CAMD Nanofabrication Infrastructure  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route Segments (notCAMD Cleanroom ChemicalHome :: News

208

CAMD Nanofabrication Links  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route Segments (notCAMD Cleanroom ChemicalHome ::

209

CAMD Nanofabrication Links  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route Segments (notCAMD Cleanroom ChemicalHome

210

CAMD Nanofabrication Research  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route Segments (notCAMD Cleanroom

211

Superconductive tunnel junction integrated circuit  

SciTech Connect (OSTI)

Josephson Junction integrated circuits of the current injection type and magnetically controlled type utilize a superconductive layer that forms both Josephson Junction electrode for the Josephson Junction devices on the integrated circuit as well as a ground plane for the integrated circuit. Large area Josephson Junctions are utilized for effecting contact to lower superconductive layers and islands are formed in superconductive layers to provide isolation between the groundplane function and the Josephson Junction electrode function as well as to effect crossovers. A superconductor-barrier-superconductor trilayer patterned by local anodization is also utilized with additional layers formed thereover. Methods of manufacturing the embodiments of the invention are disclosed.

Jillie, D.W. Jr.; Smith, L.N.

1984-02-07T23:59:59.000Z

212

Superconducting structure with layers of niobium nitride and aluminum nitride  

DOE Patents [OSTI]

A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources.

Murduck, James M. (Lisle, IL); Lepetre, Yves J. (Lauris, FR); Schuller, Ivan K. (Woodridge, IL); Ketterson, John B. (Evanston, IL)

1989-01-01T23:59:59.000Z

213

Superconducting structure with layers of niobium nitride and aluminum nitride  

DOE Patents [OSTI]

A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources. 8 figs.

Murduck, J.M.; Lepetre, Y.J.; Schuller, I.K.; Ketterson, J.B.

1989-07-04T23:59:59.000Z

214

Novel rf mems tunable filters with adjustable spurious suppression  

E-Print Network [OSTI]

This thesis presents the theory and design of fixed and Radio Frequency (RF) Microelectromechanical Systems (MEMS) -based tunable microwave filters for RF and microwave applications. The methodology for the design of coupled resonator filters...

Sekar, Vikram

2009-05-15T23:59:59.000Z

215

A day in the life of the RF spectrum  

E-Print Network [OSTI]

There is a misguided perception that RF spectrum space is fully allocated and fully used though even a superficial study of actual spectrum usage by measuring local RF energy shows it largely empty of radiation. Traditional ...

Cooley, James E. (James Edward)

2005-01-01T23:59:59.000Z

216

Design and fabrication of an RF power LDMOSFET on SOI  

E-Print Network [OSTI]

This thesis studied thin-film Silicon-on-Insulator (SOI) LDMOSFET technology for RF power amplifier applications. To conduct this study, two generations of SOI RF power devices for portable wireless systems were designed ...

Fiorenza, James G. (James George), 1972-

2002-01-01T23:59:59.000Z

217

Superconducting magnetic coil  

DOE Patents [OSTI]

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.

Aized, D.; Schwall, R.E.

1999-06-22T23:59:59.000Z

218

Superconductivity, Superfluidity and Holography  

E-Print Network [OSTI]

This is a concise review of holographic superconductors and superfluids. We highlight some predictions of the holographic models and the emphasis is given to physical aspects rather than to the technical details, although some references to understand the latter are systematically provided. We include gapped systems in the discussion, motivated by the physics of high-temperature superconductivity. In order to do so we consider a compactified extra dimension (with radius R), or, alternatively, a dilatonic field. The first setup can also be used to model cylindrical superconductors; when these are probed by an axial magnetic field a universal property of holography emerges: while for large R (compared to the other scales in the problem) non-local operators are suppressed, leading to the so called Little-Parks periodicity, the opposite limit shows non-local effects, e.g. the uplifting of the Little-Parks periodicity. This difference corresponds in the gravity side to a Hawking-Page phase transition.

Alberto Salvio

2013-01-16T23:59:59.000Z

219

Spinning superconducting electrovacuum soliton  

E-Print Network [OSTI]

In nonlinear electrodynamics coupled to general relativity and satisfying the weak energy condition, a spherically symmetric electrically charged electrovacuum soliton has obligatory de Sitter center in which the electric field vanishes while the energy density of electromagnetic vacuum achieves its maximal value. De Sitter vacuum supplies a particle with the finite positive electromagnetic mass related to breaking of space-time symmetry from the de Sitter group in the origin. By the G\\"urses-G\\"ursey algorithm based on the Newman-Trautman technique it is transformed into a spinning electrovacuum soliton asymptotically Kerr-Newman for a distant observer. De Sitter center becomes de Sitter equatorial disk which has both perfect conductor and ideal diamagnetic properties. The interior de Sitter vacuum disk displays superconducting behavior within a single spinning soliton. This behavior found for an arbitrary nonlinear lagrangian ${\\cal L}(F)$, is generic for the class of regular spinning electrovacuum solutions describing both black holes and particle-like structures.

Irina Dymnikova

2006-07-24T23:59:59.000Z

220

Superconducting magnetic coil  

DOE Patents [OSTI]

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

Aized, Dawood (Marlboro, MA); Schwall, Robert E. (Northborough, MA)

1999-06-22T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Superconducting magnetic energy storage  

SciTech Connect (OSTI)

Recent programmatic developments in Superconducting Magnetic Energy Storage (SMES) have prompted renewed and widespread interest in this field. In mid 1987 the Defense Nuclear Agency, acting for the Strategic Defense Initiative Office, issued a request for proposals for the design and construction of SMES Engineering Test Model (ETM). Two teams, one led by Bechtel and the other by Ebasco, are now engaged in the first phase of the development of a 10 to 20 MWhr ETM. This report presents the rationale for energy storage on utility systems, describes the general technology of SMES, and explains the chronological development of the technology. The present ETM program is outlined; details of the two projects for ETM development are described in other papers in these proceedings. The impact of high T/sub c/ materials on SMES is discussed. 69 refs., 3 figs., 3 tabs.

Hassenzahl, W.

1988-08-01T23:59:59.000Z

222

Superconducting dark energy  

E-Print Network [OSTI]

Based on the analogy with superconductor physics we consider a scalar-vector-tensor gravitational model, in which the dark energy action is described by a gauge invariant electromagnetic type functional. By assuming that the ground state of the dark energy is in a form of a condensate with the U(1) symmetry spontaneously broken, the gauge invariant electromagnetic dark energy can be described in terms of the combination of a vector and of a scalar field (corresponding to the Goldstone boson), respectively. The gravitational field equations are obtained by also assuming the possibility of a non-minimal coupling between the cosmological mass current and the superconducting dark energy. The cosmological implications of the dark energy model are investigated for a Friedmann-Robertson-Walker homogeneous and isotropic geometry for two particular choices of the electromagnetic type potential, corresponding to a pure electric type field, and to a pure magnetic field, respectively. The time evolution of the scale fact...

Liang, Shi-Dong

2015-01-01T23:59:59.000Z

223

Onset of surface superconductivity  

SciTech Connect (OSTI)

We examine the onset of superconductivity in the surface region of a metal. Surface effects are particularly important in systems with a short bulk coherence length {xi}{sub 0}. We show that, to the accuracy of the calculation, the surface transition temperature {ital T}{sub {ital c}{ital S}} equals the bulk transition temperature {ital T}{sub {ital c}{ital B}} if the electron-electron interaction is of the standard BCS form, i.e., a single attractive square well, extending up to some critical energy {omega}{sub 0} much smaller than the Fermi energy {var epsilon}{sub {ital F}}. If one takes into account, in addition, the repulsive part of the interaction extending beyond {omega}{sub 0} up to energies of order {var epsilon}{sub {ital F}}, then one may have {ital T}{sub {ital c}{ital S}}{gt}{ital T}{sub {ital c}{ital B}} in certain cases, although, due to restrictions imposed on the parameter values by various physical conditions, the relative increase of {ital T}{sub {ital c}} is very small, typically 10{sup {minus}3}, at least in the weak coupling limit. However, we also find a considerable gap enhancement, of order 20%, near the surface which could be of interest for critical-current measurements. Therefore we suggest an experimental reexamination of systems with short {xi}{sub 0}, i.e., superconducting degenerate semiconductors and the new high-{ital T}{sub {ital c}} oxides in confined geometries where the surface-to-volume ratio is non-negligible.

Giamarchi, T.; Beal-Monod, M.T. (Laboratoire de Physique des Solides, Universite Paris-Sud 91405 Orsay, (France)); Valls, O.T. (Laboratoire de Physique des Solides, Universite Paris-Sud, 91405 Orsay, (France) Center for the Science and Application of Superconductivity, School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (USA))

1990-06-01T23:59:59.000Z

224

Mixed-mu superconducting bearings  

DOE Patents [OSTI]

A mixed-mu superconducting bearing including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure.

Hull, John R. (Hinsdale, IL); Mulcahy, Thomas M. (Western Springs, IL)

1998-01-01T23:59:59.000Z

225

Mixed-mu superconducting bearings  

DOE Patents [OSTI]

A mixed-mu superconducting bearing is disclosed including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure. 9 figs.

Hull, J.R.; Mulcahy, T.M.

1998-03-03T23:59:59.000Z

226

EIS-0138: Superconducting Super Collider  

Broader source: Energy.gov [DOE]

The U.S. Department of Energy developed this EIS to analyze the potential environmental impacts of constructing the Superconducting Super Collider, a large proton accelerator, at each of seven alternative locations.

227

On the theory of superconductivity   

E-Print Network [OSTI]

The phenomenon of superconductivity has so for defied all attempts of explanation since it was first discovered in 1911. Although two phenomenological theories have been put forward and proved very successful, yet no atomic theories based on quantum...

Cheng, Kai-Chia

228

Configurations for short period rf undulators  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Several configurations for rf undulators energized at millimeter wavelengths and designed to produce coherent nanometer radiation from sub-GeV electron beams are analyzed and compared with one another. These configurations include a traveling-wave resonant ring, a standing wave resonator, and a resonator operating close to cutoff.

Kuzikov, S. V.; Jiang, Y.; Marshall, T. C.; Sotnikov, G. V.; Hirshfield, J. L.

2013-07-01T23:59:59.000Z

229

Cw rf operation of the FMIT RFQ  

SciTech Connect (OSTI)

The 80-MHz RFQ for the Fusion Materials Irradiation Test Facility prototype accelerator has been rf conditioned for cw operation to the design field level of 17.5 MV/m (1.68 x Kilpatrick limit). Experimental results and operating experience will be discussed.

Fazio, M.V.; Brandeberry, F.E.

1985-01-01T23:59:59.000Z

230

Emittance control in rf cavities and solenoids  

E-Print Network [OSTI]

We study emittance growth for transport of uniform and Gaussian beams of particles in rf cavities and solenoids and show analytically its dependence on initial beam parameters. Analytical results are confirmed with simulation studies over a broad range of different initial beams.

Eshraqi, Mohammad; Lombardi, Alessandra M

2009-01-01T23:59:59.000Z

231

Process for producing clad superconductive materials  

DOE Patents [OSTI]

A process for fabricating superconducting composite wire by the steps of placing a superconductive precursor admixture capable of undergoing a self propagating combustion in stoichiometric amounts sufficient to form a superconductive product within a metal tube, sealing one end of said tube, igniting said superconductive precursor admixture whereby said superconductive precursor admixture endburns along the length of the admixture, and cross-section reducing said tube at a rate substantially equal to the rate of burning of said superconductive precursor admixture and at a point substantially planar with the burnfront of the superconductive precursor mixture, whereby a clad superconductive product is formed in situ, the product characterized as superconductive without a subsequent sintering stage, is disclosed.

Cass, Richard B. (Ringoes, NJ); Ott, Kevin C. (Los Alamos, NM); Peterson, Dean E. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

232

The challenge of unconventional superconductivity.  

SciTech Connect (OSTI)

During the past few decades, several new classes of superconductors have been discovered that do not appear to be related to traditional superconductors. The source of the superconductivity of these materials is likely different from the electron-ion interactions that are at the heart of conventional superconductivity. Developing a rigorous theory for any of these classes of materials has proven to be a difficult challenge and will remain one of the major problems in physics in the decades to come.

Norman, M. R. (Materials Science Division)

2011-04-08T23:59:59.000Z

233

Superconducting pipes and levitating magnets  

E-Print Network [OSTI]

Motivated by a beautiful demonstration of the Faraday's and Lenz's law in which a small neodymium magnet falls slowly through a conducting non-ferromagnetic tube, we consider the dynamics of a magnet falling through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be suspended over the front edge. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius $a$ and length $L \\approx a$ decays, in the axial direction, with a characteristic length $\\xi \\approx 0.26 a$. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices, SQUIDs. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.

Yan Levin; Felipe B. Rizzato

2006-09-15T23:59:59.000Z

234

Progress on Superconducting Magnets for the MICE Cooling Channel  

SciTech Connect (OSTI)

The muon ionization cooling experiment (MICE) consists of a target, a beam line, a pion decay channel, the MICE cooling channel. Superconducting magnets are used in the pion decay channel and the MICE cooling channel. This report describes the MICE cooling channel magnets and the progress in the design and fabrication of these magnets. The MICE cooling channel consists of three types of superconducting solenoids; the spectrometer solenoids, the coupling solenoids and the focusing solenoids. The three types of magnets are being fabricated in he United States, China, and the United Kingdom respectively. The spectrometer magnets are used to analyze the muon beam before and after muon cooling. The coupling magnets couple the focusing sections and keep the muon beam contained within the iris of the RF cavities that re used to recover the muon momentum lost during ionization cooling. The focusing magnets focus the muon beam in the center of a liquid hydrogen absorber. The first of the cooling channel magnets will be operational in MICE in the spring of 2010.

Green, Michael A; Virostek, Steve P.; Li, Derun; Zisman, Michael S.; Wang, Li; Pan, Heng; Wu, Hong; Guo, XingLong; Xu, FengYu; Liu, X. K.; Zheng, S. X.; Bradshaw, Thomas; Baynham, Elwyn; Cobb, John; Lau, Wing; Lau, Peter; Yang, Stephanie Q.

2009-09-09T23:59:59.000Z

235

Superconducting laser photocathode RF gun at BNL | U.S. DOE Office...  

Office of Science (SC) Website

Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26Germantown Building 1000 Independence...

236

RF CAVITY PERFORMANCE in the ISAC-II SUPERCONDUCTING HEAVY ION LINAC  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, and 323 K.Office ofMayPVREPORT TOREVIEWREVISIONOct.

237

Superconducting laser photocathode RF gun at BNL | U.S. DOE Office of  

Office of Science (SC) Website

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadoreConnecticutPhotos of AECSign Up for E-mailScience (SC)

238

High-frequency absorption of the dynamic mixed state in the surface superconductivity region  

SciTech Connect (OSTI)

We analyze the absorption of a high-frequency electromagnetic field in the type II superconductor Pb{sub 0.8}In{sub 0.2} in magnetic fields H{sub c2} < H < H{sub c3}. The absorption component proportional to the rate of variation of the external magnetic field is detected. We assume that this absorption component is associated with the dynamic mixed state of the superconducting shell containing 2D magnetic flux vortices (Kulik vortices). The motion of these vortices under the action of the critical current ensures the required difference between the external and internal magnetic inductions of the superconducting shell upon a change in the external magnetic field. This model correctly describes the observed behavior of absorption of rf electromagnetic radiation.

Berezin, V. A., E-mail: berezin@iptm.ru; Tulin, V. A., E-mail: tulin@iptm.ru [Russian Academy of Sciences, Institute of Microelectronics Technology and High-Purity Materials (Russian Federation)

2013-03-15T23:59:59.000Z

239

Chapter 54. Superconducting Circuits and Quantum Computing Superconducting Circuits and Quantum Computing  

E-Print Network [OSTI]

Chapter 54. Superconducting Circuits and Quantum Computing 54-1 Superconducting Circuits. William D. Oliver (MIT Lincoln Laboratory Senior Staff Member, RLE affiliate) Overview: Superconducting computer. Our qubit species of choice is the superconducting persistent-current (PC) qubit (also known

240

Conceptual design of an L-band recirculating superconducting traveling wave accelerating structure for ILC  

SciTech Connect (OSTI)

With this paper, we propose the conceptual design of a traveling wave accelerating structure for a superconducting accelerator. The overall goal is to study a traveling wave (TW) superconducting (SC) accelerating structure for ILC that allows an increased accelerating gradient and, therefore reduction of the length of the collider. The conceptual studies were performed in order to optimize the acceleration structure design by minimizing the surface fields inside the cavity of the structure, to make the design compatible with existing technology, and to determine the maximum achievable gain in the accelerating gradient. The proposed solution considers RF feedback system redirecting the accelerating wave that passed through the superconducting traveling wave acceleration (STWA) section back to the input of the accelerating structure. The STWA structure has more cells per unit length than a TESLA structure but provides an accelerating gradient higher than a TESLA structure, consequently reducing the cost. In this paper, the STWA cell shape optimization, coupler cell design and feedback waveguide solution are considered. We also discuss the field flatness in the superconducting TW structure, the HOM modes and multipactor performance have been studied as well. The proposed TW structure design gives an overall 46% gain over the SW ILC structure if the 10 m long TW structure is employed.

Avrakhov, P.; Kanareykin, A.; Liu, Z.; Kazakov, S.; /KEK, Tsukuba; Solyak, N.; /Fermilab; Yakovlev, V.; /Omega-P, New Haven /Yale U.; Gai, W.; /Argonne

2007-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Superconducting Cable Termination  

DOE Patents [OSTI]

Disclosed is a termination that connects high temperature superconducting (HTS) cable immersed in pressurized liquid nitrogen to high voltage and neutral (shield) external bushings at ambient temperature and pressure. The termination consists of a splice between the HTS power (inner) and shield (outer) conductors and concentric copper pipes which are the conductors in the termination. There is also a transition from the dielectric tape insulator used in the HTS cable to the insulators used between and around the copper pipe conductors in the termination. At the warm end of the termination the copper pipes are connected via copper braided straps to the conventional warm external bushings which have low thermal stresses. This termination allows for a natural temperature gradient in the copper pipe conductors inside the termination which enables the controlled flashing of the pressurized liquid coolant (nitrogen) to the gaseous state. Thus the entire termination is near the coolant supply pressure and the high voltage and shield cold bushings, a highly stressed component used in most HTS cables, are eliminated. A sliding seal allows for cable contraction as it is cooled from room temperature to ˜72-82 K. Seals, static vacuum, and multi-layer superinsulation minimize radial heat leak to the environment.

Sinha, Uday K. (Carrollton, GA); Tolbert, Jerry (Newnan, GA)

2005-08-30T23:59:59.000Z

242

Improved superconducting magnet wire  

DOE Patents [OSTI]

This invention is directed to a superconducting tape or wire composed of alternating layers of copper and a niobium-containing superconductor such as niobium of NbTi, Nb/sub 3/Sn or Nb/sub 3/Ge. In general, each layer of the niobium-containing superconductor has a thickness in the range of about 0.05 to 1.5 times its coherence length (which for Nb/sub 3/Si is 41 A) with each copper layer having a thickness in the range of about 170 to 600 A. With the use of very thin layers of the niobium composition having a thickness within the desired range, the critical field (H/sub c/) may be increased by factors of 2 to 4. Also, the thin layers of the superconductor permit the resulting tape or wire to exhibit suitable ductility for winding on a magnet core. These compositions are also characterized by relatively high values of critical temperature and therefore will exhibit a combination of useful properties as superconductors.

Schuller, I.K.; Ketterson, J.B.

1983-08-16T23:59:59.000Z

243

Superconducting digital logic amplifier  

SciTech Connect (OSTI)

This paper describes a superconducting digital logic amplifier for interfacing between a Josephson junction logic circuit having output current and a higher voltage semiconductor circuit input. The amplifier comprising: an input terminal for connection to a ; an output terminal for connection to a semiconductor circuit input; an input, lower critical current, Josephson junction having first and second terminals; a first series string of at least three lower critical current Josephson junctions. The first series string being connected to the first terminal of the input Josephson junction such that the first series string is in series with the input Josephson junction to provide a series combination. The input terminal being connected to the first terminal of the input Josephson junction, and with the critical current of the lower critical current Josephson junctions of the input Josephson junction and the first series Josephson junctions being less than the output current of the low voltage Josephson junction circuit; a second series string of at least four higher critical current Josephson junctions. The second string being connected in parallel with the series combination to provide parallel strings having an upper common connection and a lower common connection. The lower common connection being connected to the second terminal of the input Josephson junction and the upper common connection being connected to the output terminal; and a pulsed DC current source connected the parallel strings at the upper common connection. The DC current source having a current at least equal to the critical current of the higher critical current Josephson junctions.

Przybysz, J.X.

1989-08-22T23:59:59.000Z

244

HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network [OSTI]

D. C. 'Niobium-Titanium Superconducting Material s ', in S.Nb -Ti and Nb3Sn superconductors. , •• ,""" s. S. Clamp, Tie14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.

Taylor, C.

2011-01-01T23:59:59.000Z

245

Superconducting Partnership with Readiness Review Update  

E-Print Network [OSTI]

1 Superconducting Partnership with Industry: Readiness Review Update Mike Gouge, ORNL Steve Ashworth, LANL Paul Bakke, DOE-Golden DOE 2004 Superconductivity Peer Review July 27-29, 2004 #12;2 SPI

246

ORNL/HTSPC-10 ORNL Superconducting  

E-Print Network [OSTI]

ORNL/HTSPC-10 ORNL Superconducting Technology Program for Electric Power Systems Annual Report http://www.doe.gov/bridge #12;ORNL/HTSPC-10 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC POWER

247

A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER  

E-Print Network [OSTI]

A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER FOR PRODUCTION OF NEUTRON-RICH NUCLEI ( 136 Xe Superconducting Cyclotron Laboratory's weekly \\Green Sheet," 30 July 1999 #12; c Thomas W. O'Donnell 2000 All

O'Donnell, Tom

248

ORNL/HTSPC-12 ORNL Superconducting Technology  

E-Print Network [OSTI]

ORNL/HTSPC-12 ORNL Superconducting Technology Program for Electric Power Systems Annual Report States Government or any agency thereof. #12;ORNL/HTSPC-12 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM

249

ORNL/HTSPC-14 ORNL Superconducting Technology  

E-Print Network [OSTI]

ORNL/HTSPC-14 ORNL Superconducting Technology Program for Electric Power Systems Annual Report States Government or any agency thereof. #12;ORNL/HTSPC-14 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM

250

ORNL/HTSPC-18 ORNL Superconducting Technology  

E-Print Network [OSTI]

ORNL/HTSPC-18 ORNL Superconducting Technology Program for Electric Power Systems Annual Report Government or any agency thereof. #12;ORNL/HTSPC-18 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC

251

A Numerical Treatment of the Rf SQUID: I. General Properties andNoise Energy  

SciTech Connect (OSTI)

We investigate the characteristics and noise performance of rf Superconducting Quantum Interference Devices (SQUIDs) by solving the corresponding Langevin equations numerically and optimizing the model parameters with respect to noise energy. After introducing the basic concepts of the numerical simulations, we give a detailed discussion of the performance of the SQUID as a function of all relevant parameters. The best performance is obtained in the crossover region between the dispersive and dissipative regimes, characterized by an inductance parameter {beta}{prime}{sub L} {triple_bond} 2{pi}LI{sub 0}/{Phi}{sub 0} {approx} 1; L is the loop inductance, I{sub 0} the critical current of the Josephson junction, and {phi}{sub 0} the flux quantum. In this regime, which is not well explored by previous analytical approaches, the lowest (intrinsic) values of noise energy are a factor of about 2 above previous estimates based on analytical approaches. However, several other analytical predictions, such as the inverse proportionality of the noise energy on the tank circuit quality factor and the square of the coupling coefficient between the tank circuit and the SQUID loop, could not be well reproduced. The optimized intrinsic noise energy of the rf SQUID is superior to that of the dc SQUID at all temperatures. Although for technologically achievable parameters this advantage shrinks, particularly at low thermal fluctuation levels, we give an example for realistic parameters that leads to a noise energy comparable to that of the dc SQUID even in this regime.

Kleiner, Reinhold; Koelle, Dieter; Clarke, John

2007-01-15T23:59:59.000Z

252

RUGGED CERAMIC WINDOW FOR RF APPLICATIONS  

SciTech Connect (OSTI)

High-current RF cavities that are needed for many accelerator applications are often limited by the power transmission capability of the pressure barriers (windows) that separate the cavity from the power source. Most efforts to improve RF window design have focused on alumina ceramic, the most popular historical choice, and have not taken advantage of new materials. Alternative window materials have been investigated using a novel Merit Factor comparison and likely candidates have been tested for the material properties which will enable construction in the self-matched window configuration. Window assemblies have also been modeled and fabricated using compressed window techniques which have proven to increase the power handling capability of waveguide windows. Candidate materials have been chosen to be used in fabricating a window for high power testing at Thomas Jefferson National Accelerator Facility.

MIKE NEUBAUER

2012-11-01T23:59:59.000Z

253

An Efficient RF Source for Jlab  

SciTech Connect (OSTI)

We propose the development of a highly reliable high efficiency RF source for JLAB with a lower lifetime cost operating at 80% efficiency with system operating costs of about 0.7M$/year for the 6 GeV machine. The design of the RF source will be based upon two injection locked magnetrons in a novel combining architecture for amplitude modulation and a cross field amplifier (CFA) as an output tube for the 12 GeV upgrade. A cost analysis including efficiency and reliability will be performed to determine the optimum system architecture. Several different system architectures will be designed and evaluated for a dual injection locked magnetron source using novel combining techniques and possibly a CFA as the output tube. A paper design for the 1497 MHz magnetron system will be completed. The optimum system architecture with all relevant specifications will be completed so that a prototype can be built.

Neubauer, M. [Muons, Inc.; Dudas, A. [Muons, Inc.; Rimmer, Robert A. [JLAB; Wang, Haipeng [JLAB

2013-12-01T23:59:59.000Z

254

ILC RF System R and D  

SciTech Connect (OSTI)

The Linac Group at SLAC is actively pursuing a broad range of R&D to improve the reliability and reduce the cost of the L-band (1.3 GHz) rf system proposed for the ILC linacs. Current activities include the long-term evaluation of a 120 kV Marx Modulator driving a 10 MW Multi-Beam Klystron, design of a second-generation Marx Modulator, testing of a sheet-beam gun and beam transport system for a klystron, construction of an rf distribution system with remotely-adjustable power tapoffs, and development of a system to combine the power from many klystrons in low-loss circular waveguide where it would be tapped-off periodically to power groups of cavities. This paper surveys progress during the past few years.

Adolphsen, Chris; /SLAC

2012-07-03T23:59:59.000Z

255

The new RF sources for accelerators  

SciTech Connect (OSTI)

Several new RF sources are being developed for accelerator and collider applications. Assembly is nearing completion of a multiple beam inductive output tube at 352 MHz. An annular beam klystron is being developed to produce 10 MW pulses at 1.3 GHz. The annular beam approach provides significant cost reduction over similar multiple beam devices. Fabrication is underway on a 10 kW, periodic permanent magnet klystron at 2.815 GHz. Permanent magnets eliminate the solenoid and associated power supplies and cooling requirements to reduce operational cost. Investigations are beginning on a novel approach for driving accelerator cavities using pulse shaping to increase coupling efficiency and dramatically reduce RF power requirements.

Ives, Lawrence; Read, Michael; Ferguson, Patrick; Marsden, David; Collins, George; Jackson, R. H.; Bui, Thuc; Kimura, Takuji; Eisen, Edward [Calabazas Creek Research, Inc., 690 Port Drive, San Mateo, CA, 94404, (650) 312-9575 (United States); Communications and Power Industries, LLC., 811 Hansen Way, Palo Alto, CA94304 (United States)

2012-12-21T23:59:59.000Z

256

Fast superconducting magnetic field switch  

DOE Patents [OSTI]

The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

1996-01-01T23:59:59.000Z

257

A unified theory of superconductivity  

E-Print Network [OSTI]

In this paper, we study the reliability of BCS theory as a scientific explanation of the mystery of superconductivity. It is shown clearly that the phonon-mediated BCS theory is fundamentally incorrect. Two kinds of glues, pairing (pseudogap) glue and superconducting glue, are suggested based on a real space Coulomb confinement effect. The scenarios provide a unified explanation of the pairing symmetry, pseudogap and superconducting states, charge stripe order, spin density wave (SDW), checkerboard-type charge-ordered phase, magic doping fractions and vortex structures in conventional and unconventional (the high-Tc cuprates and MgB2) superconductors. The theory agrees with the existence of a pseudogap in high-temperature superconductors, while no pseudogap feature could be observed in MgB2 and most of the conventional superconductors. Our results indicate that the superconducting phase can coexist with a inclined hexagonal vortex lattice in pure MgB2 single crystal with a charge carrier density ps=1.49*10^{22}/cm^{3}. Finally, the physical reasons why the good conductors (for example, Ag, Au, and Cu) and the overdoped high-Tc superconductors are non-superconducting are also explored.

Xiuqing Huang

2008-09-22T23:59:59.000Z

258

Radio frequency (RF) heated supersonic flow laboratory  

SciTech Connect (OSTI)

A unique supersonic flow apparatus which employs an inductively-coupled, radio frequency (RF) torch to supply high enthalpy source gas to the nozzle inlet is described. The main features of this system are the plasma tube, a cooled nozzle assembly, and a combustion/expansion chamber with a heat exchanger. A description of these components with current test data is presented. In addition, a discussion of anticipated experiments utilizing this system is included.

Wantuck, P.; Watanabe, H.

1990-01-01T23:59:59.000Z

259

RF Micro Devices | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to: navigation, search RAPIDColoradosource History View New PagesElectron srlRF Micro Devices

260

RF Gun Photocathode Research at SLAC  

SciTech Connect (OSTI)

LCLS is presently operating with a third copper photocathode in the original rf gun, with a quantum efficiency (QE) of {approx}1 x 10{sup -4} and projected emittance {gamma}{var_epsilon}{sub x,y} = 0.45 {micro}m at 250 pC bunch charge. The spare LCLS gun is installed in the SLAC Accelerator Structure Test Area (ASTA), fully processed to high rf power. As part of a wider photocathode R and D program, a UV laser system and additional gun diagnostics are being installed at ASTA to measure QE, QE lifetime, and electron beam emittance under a variety of operating conditions. The near-term goals are to test and verify the spare photocathode production/installation sequence, including transfer from the final holding chamber to the rf gun. Mid- and longer-term goals include development of a rigorous understanding of plasma and laser-assisted surface conditioning and investigation of new, high-QE photocathode materials. In parallel, an x-ray photoemission spectroscopy station is nearing completion, to analyze Cu photocathode surface chemistry. In this paper we review the status and anticipated operating parameters of ASTA and the spectroscopy test chamber.

Jongewaard, E.; Akre, R.; Brachmann, A.; Corbett, J.; Gilevich, S.; Grouev, K.; Hering, P.; P.Krejcik,; Lewandowski, J.; Loos, H.; Montagne, T.; Sheppard, J.C.; Stefan, P.; Vlieks, A.; Weathersby, S.; Zhou, F.; /SLAC

2012-05-16T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Superconducting Topological Fluids in Josephson Junction Arrays  

E-Print Network [OSTI]

We argue that the frustrated Josephson junction arrays may support a topologically ordered superconducting ground state, characterized by a non-trivial ground state degeneracy on the torus. This superconducting quantum fluid provides an explicit example of a system in which superconductivity arises from a topological mechanism rather than from the usual Landau-Ginzburg mechanism.

M. Cristina Diamantini; Pasquale Sodano; Carlo A. Trugenberger

2006-04-21T23:59:59.000Z

262

Superconductivity in iron compounds G. R. Stewart  

E-Print Network [OSTI]

of the superconductivity in this new class of compounds. These iron pnictide and chalcogenide (FePn/Ch) superconductors-phonon coupled ``conventional'' superconductors. Clearly, superconductivity and magnetism or magnetic of magnetism and superconductivity in FePn/Ch superconductors 1606 D. Tc and TS=TSDW versus pressure 1607 1

Wu, Zhigang

263

SUPERCONDUCTING MAGNETOMETERS By J. E. MERCEREAU,  

E-Print Network [OSTI]

13. SUPERCONDUCTING MAGNETOMETERS By J. E. MERCEREAU, California Institute of Technology, Alfred. P in superconducting tunnel junctions. Various structures have been fabricated in which this quantum relation dominates been the principal hallmark of the phenomena of superconductivity. It was, in fact, this effect which

Paris-Sud XI, Université de

264

ORNL/HTSPC-16 ORNL Superconducting Technology  

E-Print Network [OSTI]

ORNL/HTSPC-16 ORNL Superconducting Technology Program for Electric Power Systems Annual Report government or any agency thereof. #12;ORNL/HTSPC-16 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC ................................................................ 1-1 1.1 Ultera/ORNL HTS Cable Superconductivity Partnership with Industry (SPI

265

ORNL/HTSPC-15 ORNL Superconducting Technology  

E-Print Network [OSTI]

ORNL/HTSPC-15 ORNL Superconducting Technology Program for Electric Power Systems Annual Report government or any agency thereof. #12;ORNL/HTSPC-15 ORNL SUPERCONDUCTING TECHNOLOGY PROGRAM FOR ELECTRIC Manuscript Completed: March 2004 Date Published: June 2004 Prepared for the Superconductivity Program

266

Bifurcation to vortex solutions in superconducting lms  

E-Print Network [OSTI]

Bifurcation to vortex solutions in superconducting #12;lms T. Boeck #3; S.J. Chapman y Mathematical state to a superconducting state in a decreasing magnetic #12;eld is studied for a slab geometry of these behaviours will occur in practice. 1 Introduction If a superconducting body is placed in a suÃ?ciently strong

Chapman, Jon

267

Freely oriented portable superconducting magnet  

DOE Patents [OSTI]

A freely oriented portable superconducting magnet is disclosed. Coolant is supplied to the superconducting magnet from a repository separate from the magnet, enabling portability of the magnet. A plurality of support assemblies structurally anchor and thermally isolate the magnet within a thermal shield. A plurality of support assemblies structurally anchor and thermally isolate the thermal shield within a vacuum vessel. The support assemblies restrain movement of the magnet resulting from energizing and cooldown, as well as from changes in orientation, enabling the magnet to be freely orientable.

Schmierer, Eric N. (Los Alamos, NM); Prenger, F. Coyne (Los Alamos, NM); Hill, Dallas D. (Los Alamos, NM)

2010-01-12T23:59:59.000Z

268

Design and Manufacture of the RF Power Supply and RF Transmission Line for SANAEM Project Prometheus  

E-Print Network [OSTI]

A 1-5 MeV proton beamline is being built by the Turkish Atomic Energy Authority in collaboration with a number of graduate students from different universities. The most important aspect of the project, is to acquire the design ability and manufacturing capability of all the components locally. SPP will be an accelerator and beam diagnostics test facility and it will also serve the detector development community with its low beam current. This paper discusses the design and construction of the RF power supply and the RF transmission line components such as its waveguide converters and its circulator.

Turemen, G; Unel, G; Alacakir, A

2015-01-01T23:59:59.000Z

269

A STATE VARIABLE DESCRIPTION OF THE RHIC RF CONTROL LOOPS.  

SciTech Connect (OSTI)

The beam transfer function changes during the RHIC ramp. The response of the RF control loops changes as a result. A state-variable description of the beam and the RF control loops was developed. This description was used to generate a set of feedback matrices that keeps the response of the RF control loops constant during the ramp. This paper describes the state-variable description and its use in determining the K matrices.

SCHULTHEISS,C.; BRENNAN,J.M.

2002-06-02T23:59:59.000Z

270

RF Gun cavities cooling regime study. K. Floettmann1  

E-Print Network [OSTI]

RF power of Pa 68kW corre- sponds to a heat load of 300kW m . To remove such a high heat value from of RF fields in the cavity at an operating frequency is calculated in the usual way. The temperature) with the boundary condition at the RF cavity surface: kc(ngradT) = Ps, (2) where kc = 391 W m·K is the heat

271

Vacuum Technology for Superconducting Devices  

E-Print Network [OSTI]

The basic notions of vacuum technology for superconducting applications are presented, with an emphasis on mass and heat transport in free molecular regimes. The working principles and practical details of turbomolecular pumps and cryopumps are introduced. The specific case of the Large Hadron Collider’s cryogenic vacuum system is briefly reviewed.

Chiggiato, P

2014-01-01T23:59:59.000Z

272

Fractal Superconductivity near Localization Threshold  

E-Print Network [OSTI]

Fractal Superconductivity near Localization Threshold Mikhail Feigel'man Landau Institute, Moscow-electron states are extended but fractal and populate small fraction of the whole volume How BCS theory should be modified to account for eigenstates fractality ? #12;Mean-Field Eq. for Tc #12;#12;3D Anderson model: = 0

Fominov, Yakov

273

Superconducting flux flow digital circuits  

DOE Patents [OSTI]

A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

1995-02-14T23:59:59.000Z

274

Superconducting flux flow digital circuits  

DOE Patents [OSTI]

A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs). Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics.

Hietala, Vincent M. (Placitas, NM); Martens, Jon S. (Sunnyvale, CA); Zipperian, Thomas E. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

275

Dynamical properties of superconducting nanowires  

SciTech Connect (OSTI)

The dynamical properties of thin superconducting wires (nanowires) are studied using numerical simulations based on a one-dimensional time-dependent Ginzburg-Landau equation, which is modified by introducing an order parameter u characterizing the 'purity' of the superconductor material. It is established that relatively long nanowires (with lengths much greater than the coherence length) made of a 'pure' superconductor (u > 1) are characterized by two critical current density values: j{sub c1} and j{sub c2}. For j < j{sub c1}, the total current is entirely superconducting, whereas for j > j{sub c2}, the current is purely normal. In the intermediate region of current densities, j{sub c1} < j < j{sub c2}, the total current contains both superconducting and normal components (mixed state) and the nanowire exhibits the generation of high-frequency electromagnetic waves. The current-voltage characteristics are constructed and the radiation spectrum is obtained. The properties of short superconducting nanowires (with lengths on the order of the coherence length) coincide with those of the Josephson junction. In the case of an 'impure' superconductor (u < 1), the nanowire is characterized by a single critical current density.

Nikolaev, S. V.; Yugay, K. N. [Omsk State University (Russian Federation)], E-mail: yugay_klimenty@mail.ru

2006-02-15T23:59:59.000Z

276

Multi-Physics Analysis of the Fermilab Booster RF Cavity  

SciTech Connect (OSTI)

After about 40 years of operation the RF accelerating cavities in Fermilab Booster need an upgrade to improve their reliability and to increase the repetition rate in order to support a future experimental program. An increase in the repetition rate from 7 to 15 Hz entails increasing the power dissipation in the RF cavities, their ferrite loaded tuners, and HOM dampers. The increased duty factor requires careful modelling for the RF heating effects in the cavity. A multi-physic analysis investigating both the RF and thermal properties of Booster cavity under various operating conditions is presented in this paper.

Awida, M.; Reid, J.; Yakovlev, V.; Lebedev, V.; Khabiboulline, T.; Champion, M.; /Fermilab

2012-05-14T23:59:59.000Z

277

Active high-power RF switch and pulse compression system  

DOE Patents [OSTI]

A high-power RF switching device employs a semiconductor wafer positioned in the third port of a three-port RF device. A controllable source of directed energy, such as a suitable laser or electron beam, is aimed at the semiconductor material. When the source is turned on, the energy incident on the wafer induces an electron-hole plasma layer on the wafer, changing the wafer's dielectric constant, turning the third port into a termination for incident RF signals, and. causing all incident RF signals to be reflected from the surface of the wafer. The propagation constant of RF signals through port 3, therefore, can be changed by controlling the beam. By making the RF coupling to the third port as small as necessary, one can reduce the peak electric field on the unexcited silicon surface for any level of input power from port 1, thereby reducing risk of damaging the wafer by RF with high peak power. The switch is useful to the construction of an improved pulse compression system to boost the peak power of microwave tubes driving linear accelerators. In this application, the high-power RF switch is placed at the coupling iris between the charging waveguide and the resonant storage line of a pulse compression system. This optically controlled high power RF pulse compression system can handle hundreds of Megawatts of power at X-band.

Tantawi, Sami G. (San Mateo, CA); Ruth, Ronald D. (Woodside, CA); Zolotorev, Max (Mountain View, CA)

1998-01-01T23:59:59.000Z

278

argon rf plasma: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

you for being so encouraging, for listening to and understanding the woes of RF plasma research, and for being so friendly at conferences and in the hallways. Professor...

279

Design Parameters and Commissioning of Vertical Inserts Used for Testing the XFEL Superconducting Cavities  

E-Print Network [OSTI]

The European XFEL is a new research facility currently under construction at DESY in the Hamburg area in Germany. From 2015 on, it will generate extremely intense X-ray flashes that will be used by researchers from all over the world. The superconducting XFEL linear accelerator consists of 100 accelerator modules with more than 800 RF-cavities inside. The accelerator modules, superconducting magnets and cavities will be tested in the accelerator module test facility (AMTF). This paper gives an overview of the design parameters and the commissioning of the vertical insert, used in two cryostats (XATC) of the AMTF-hall. The Insert serves as a holder for 4 nine-cell cavities. This gives the possibility to cool down 4 cavities to 2K in parallel and, consequently, to reduce the testing time. The following RF measurement, selected as quality check, will be done separately for each cavity. Afterwards the cavities will be warmed up again and will be sent to the accelerator module assembly.

J. Schaffran; Y. Bozhko; B. Petersen; D. Meissner; M. Chorowski; J. Polinski

2013-06-26T23:59:59.000Z

280

Design parameters and commissioning of vertical inserts used for testing the XFEL superconducting cavities  

SciTech Connect (OSTI)

The European XFEL is a new research facility currently under construction at DESY in the Hamburg area in Germany. From 2015 on, it will generate extremely intense X-ray flashes that will be used by researchers from all over the world. The superconducting XFEL linear accelerator consists of 100 accelerator modules with more than 800 RF-cavities inside. The accelerator modules, superconducting magnets and cavities will be tested in the accelerator module test facility (AMTF). This paper gives an overview of the design parameters and the commissioning of the vertical insert, used in two cryostats (XATC) of the AMTF-hall. The Insert serves as a holder for 4 nine-cell cavities. This gives the possibility to cool down 4 cavities to 2K in parallel and, consequently, to reduce the testing time. The following RF measurement, selected as quality check, will be done separately for each cavity. Afterwards the cavities will be warmed up again and will be sent to the accelerator module assembly.

Schaffran, J.; Bozhko, Y.; Petersen, B.; Meissner, D. [Deutsches Elektronen Synchrotron DESY, Notkestr. 85, D-22607 Hamburg (Germany); Chorowski, M.; Polinski, J. [Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland)

2014-01-29T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Design and first cold test of BNL superconducting 112 MHz QWR for electron gun applications  

SciTech Connect (OSTI)

Brookhaven National Laboratory and Niowave, Inc. have designed, fabricated, and performed the first cold test of a superconducting 112 MHz quarter-wave resonator (QWR) for electron gun experiments. The first cold test of the QWR cryomodule has been completed at Niowave. The paper discusses the cryomodule design, presents the cold test results, and outline plans to upgrade the cryomodule for future experiments. A quarter-wave resonator concept of superconducting RF (SRF) electron gun was proposed at BNL for electron cooling ion/proton beams at RHIC. QWRs can be made sufficiently compact even at low RF frequencies (long wavelengths). The long wavelength allows to produce long electron bunches, thus minimizing space charge effects and enabling high bunch charge. Also, such guns should be suitable for experiments requiring high average current electron beams. A 112 MHz QWR gun was designed, fabricated, and cold-tested in collaboration between BNL and Niowave. This is the lowest frequency SRF gun ever tested successfully. In this paper we describe the gun design and fabrication, present the cold test results, and outline plans for the cryomodule upgrade for future experiments.

Belomestnykh, S.; Ben-Zvi, I.; Boulware, C.H.; Chang, X.; Grimm, T.L.; Siegel, B.; Than, R.; Winowski, M.

2011-03-28T23:59:59.000Z

282

MICROSTRUCTURE OF SUPERCONDUCTING MGB(2).  

SciTech Connect (OSTI)

Recently, Akimitsu and co-workers [1] discovered superconductivity at 39 K in the intermetallic compound MgB{sub 2}. This discovery provides a new perspective on the mechanism for superconductivity. More specifically, it opens up possibilities for investigation of structure/properties in a new class of materials. With the exceptions of the cuprate and C{sub 60} families of compounds, MgB{sub 2} possesses the highest superconducting transition temperature T{sub c}. Its superconductivity appears to follow the BCS theory, apparently being mediated by electron-phonon coupling. The coherence length of MgB{sub 2} is reported to be longer than that of the cuprates [2]. In contrast to the cuprates, grain boundaries are strongly coupled and current density is determined by flux pinning [2,3]. Presently, samples of MgB{sub 2} commonly display inhomogeneity and porosity on the nanoscale, and are untextured. In spite of these obstacles, magnetization and transport measurements show that polycrystalline samples may carry large current densities circulating across many grains [3,4]. Very high values of critical current densities and critical fields have been recently observed in thin films [5,6]. These attributes suggest possible large scale and electronic applications. The underlying microstructure can be intriguing, both in terms of basic science and in applied areas. Subsequent to the discovery, many papers were published [1-13], most dealing with synthesis, physical properties, and theory. There have yet been few studies of microstructure and structural defects [11, 14]. A thorough understanding of practical superconducting properties can only be developed after an understanding of microstructure is gained. In this work we review transmission electron microscopy (TEM) studies of sintered MgB{sub 2} pellets [14]. Structural defects, including second phase particles, dislocations, stacking faults, and grain boundaries, are analyzed using electron diffraction, electron-energy loss spectroscopy (EELS), high resolution imaging, and structural modeling.

ZHU,Y.; LI,Q.; WU,L.; VOLKOV,V.; GU,G.; MOODENBAUGH,A.R.

2001-07-12T23:59:59.000Z

283

Sandia National Laboratories: RF & Photonics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik SpoerkeSolar Regional Test CenterCMCNational LaboratoriesRF &

284

Extremely high frequency RF effects on electronics.  

SciTech Connect (OSTI)

The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

2012-01-01T23:59:59.000Z

285

Numerical Analysis of Non-Uniformities and Anisotropy in High-Temperature Superconducting Coils  

E-Print Network [OSTI]

, critical current density (superconductivity), high-temperature superconductors, numerical analysis, superconducting coils, transport ac loss....

Hu, Di; Ainslie, Mark D.; Zou, Jin; Cardwell, David A.

2014-12-12T23:59:59.000Z

286

RF Thermal Plasma Synthesis of Ferrite Nanopowders from Metallurgical Wastes  

E-Print Network [OSTI]

RF Thermal Plasma Synthesis of Ferrite Nanopowders from Metallurgical Wastes J.Szépvölgyi1 , I Department of General Physics, Eötvös University H-1518 Budapest, P.O.B. 32 Hungary Keywords: zinc ferrite, thermal plasma, waste, XRD Abstract. RF thermal plasma synthesis of zinc-ferrite nanopowders has been

Gubicza, Jenõ

287

RF-MEMS capacitive switches with high reliability  

DOE Patents [OSTI]

A reliable long life RF-MEMS capacitive switch is provided with a dielectric layer comprising a "fast discharge diamond dielectric layer" and enabling rapid switch recovery, dielectric layer charging and discharging that is efficient and effective to enable RF-MEMS switch operation to greater than or equal to 100 billion cycles.

Goldsmith, Charles L.; Auciello, Orlando H.; Carlisle, John A.; Sampath, Suresh; Sumant, Anirudha V.; Carpick, Robert W.; Hwang, James; Mancini, Derrick C.; Gudeman, Chris

2013-09-03T23:59:59.000Z

288

Booster Synchrotron RF System Upgrade for SPEAR3  

SciTech Connect (OSTI)

Recent progress at the SPEAR3 includes the increase in stored current from 100 mA to 200 mA and top-off injection to allow beamlines to stay open during injection. Presently the booster injects 3.0 GeV beam to SPEAR3 three times a day. The stored beam decays to about 150 mA between the injections. The growing user demands are to increase the stored current to the design value of 500 mA, and to maintain it at a constant value within a percent or so. To achieve this goal the booster must inject once every few minutes. For improved injection efficiency, all RF systems at the linac, booster and SPEAR3 need to be phase-locked. The present booster RF system is basically a copy of the SPEAR2 RF system with 358.5 MHz and 40 kW peak RF power driving a 5-cell RF cavity for 1.0 MV gap voltage. These requirements entail a booster RF system upgrade to a scaled down version of the SPEAR3 RF system of 476.3 MHz with 1.2 MW cw klystron output power capabilities. We will analyze each subsystem option for their merits within budgetary and geometric space constraints. A substantial portion of the system will come from the decommissioned PEP-II RF stations.

Park, Sanghyun; /SLAC; Corbett, Jeff; /SLAC

2012-07-06T23:59:59.000Z

289

RF cavity using liquid dielectric for tuning and cooling  

DOE Patents [OSTI]

A system for accelerating particles includes an RF cavity that contains a ferrite core and a liquid dielectric. Characteristics of the ferrite core and the liquid dielectric, among other factors, determine the resonant frequency of the RF cavity. The liquid dielectric is circulated to cool the ferrite core during the operation of the system.

Popovic, Milorad (Warrenville, IL); Johnson, Rolland P. (Newport News, VA)

2012-04-17T23:59:59.000Z

290

Superconducting Cable Having A Felexible Former  

DOE Patents [OSTI]

In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

2005-03-15T23:59:59.000Z

291

Superconducting Cable Having A Flexible Former  

DOE Patents [OSTI]

In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

2005-08-30T23:59:59.000Z

292

Superconducting Transitions in Wire Network under Spatially Modulated Magnetic Field  

E-Print Network [OSTI]

The nature of phase transition in artificially structured superconducting systems such as superconducting artificially structured superconducting systems]. Introduction of the checkerboard field with amplitude #12; to the ¼ 1=2 case lifts the double degeneracy

Katsumoto, Shingo

293

Superconducting Tunnel Junctions as Direct Detectors for Submillimeter Astronomy  

E-Print Network [OSTI]

Superconducting Tunnel Junctions as Direct Detectors for Submillimeter Astronomy A Dissertation 2008 by John Daniel Teufel. All rights reserved. #12;Abstract Superconducting Tunnel Junctions on the of performance of superconducting tunnel junctions (STJ) as direct detectors for submillimeter radiation. Over

294

Superconducting magnets for muon capture and phase rotation  

E-Print Network [OSTI]

LBNL-43998 SC-MAG-683 SUPERCONDUCTING MAGNETS FOR MUONDE-AC03-76SF00098. Green SUPERCONDUCTING MAGNETS FOR MUONet ai, "The Use of Superconducting Solenoids in a Muon

Green, M.A.

2011-01-01T23:59:59.000Z

295

anisotropic superconducting gap: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Research Laboratory of a spin-density wave SDW on s superconductivity in Fe-based superconduct- ors. We show that, contrary Vavilov, Maxim G 15 A Superconductive, Low Beta Single...

296

Quadratic superconducting cosmic strings revisited  

E-Print Network [OSTI]

It has been shown that 5-dimensional general relativity action extended by appropriate quadratic terms admits a singular superconducting cosmic string solution. We search for cosmic strings endowed with similar and extended physical properties by directly integrating the non-linear matrix field equations thus avoiding the perturbative approach by which we constructed the above-mentioned \\textsl{exact} solution. The most general superconducting cosmic string, subject to some constraints, will be derived and shown to be mathematically \\textsl{unique} up to linear coordinate transformations mixing its Killing vectors. The most general solution, however, is not globally equivalent to the old one due to the existence of Killing vectors with closed orbits.

Mustapha Azreg-Aïnou

2008-02-22T23:59:59.000Z

297

Quantum memory for superconducting qubits  

SciTech Connect (OSTI)

Many protocols for quantum computation require a memory element to store qubits. We discuss the speed and accuracy with which quantum states prepared in a superconducting qubit can be stored in and later retrieved from an attached high-Q resonator. The memory fidelity depends on both the qubit-resonator coupling strength and the location of the state on the Bloch sphere. Our results show that a quantum memory demonstration should be possible with existing superconducting qubit designs, which would be an important milestone in solid-state quantum information processing. Although we specifically focus on a large-area, current-biased Josesphson-junction phase qubit coupled to the dilatational mode of a piezoelectric nanoelectromechanical disk resonator, many of our results will apply to other qubit-oscillator models.

Pritchett, Emily J.; Geller, Michael R. [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602-2451 (United States)

2005-07-15T23:59:59.000Z

298

Progress on a cryogenically cooled RF gun polarized electron source  

SciTech Connect (OSTI)

RF guns have proven useful in multiple accelerator applications. An RF gun capable of producing polarized electrons is an attractive electron source for the ILC or an electron-ion collider. Producing such a gun has proven elusive. The NEA GaAs photocathode needed for polarized electron production is damaged by the vacuum environment in an RF gun. Electron and ion back bombardment can also damage the cathode. These problems must be mitigated before producing an RF gun polarized electron source. In this paper we report continuing efforts to improve the vacuum environment in a normal conducting RF gun by cooling it with liquid nitrogen after a high temperature vacuum bake out. We also report on a design of a cathode preparation chamber to produce bulk GaAs photocathodes for testing in such a gun. Future directions are also discussed.

Fliller, R.P., III; Edwards, H.; /Fermilab

2006-08-01T23:59:59.000Z

299

The electrical and lumen output characteristics of an RF lamp  

SciTech Connect (OSTI)

Low pressure rf discharges have been studied for over a century. Their first practical application for lighting was proposed by Tesla in 1891. Since then hundreds of patents have been published attempting to implement rf lighting. However, progress in understanding rf discharge phenomena (mostly driven by plasma processing needs) and dramatic improvement in the performance/cost ratio of rf power sources have recently opened the door for development of rf light sources. Today commercial inductively coupled electrodeless lamps are offered by Matsuhita, Philips and GE. In this work the authors present measurements of the electrical characteristics and lumen output from a 2.65 MHz driven inductively coupled light source. Measurements were made on a spherical lamp of 3.125 inch diameter with a re-entrant cavity that houses a cylindrical ferrite core around which is wrapped the primary coil.

Alexandrovich, B.M.; Godyak, V.A.; Piejak, R.B. [Osram Sylvania Inc., Beverly, MA (United States)

1996-12-31T23:59:59.000Z

300

Hydrogen-filled RF Cavities for Muon Beam Cooling  

SciTech Connect (OSTI)

Ionization cooling requires low-Z energy absorbers immersed in a strong magnetic field and high-gradient, large-aperture RF cavities to be able to cool a muon beam as quickly as the short muon lifetime requires. RF cavities that operate in vacuum are vulnerable to dark-current- generated breakdown, which is exacerbated by strong magnetic fields, and they require extra safety windows that degrade cooling, to separate RF regions from hydrogen energy absorbers. RF cavities pressurized with dense hydrogen gas will be developed that use the same gas volume to provide the energy absorber and the RF acceleration needed for ionization cooling. The breakdown suppression by the dense gas will allow the cavities to operate in strong magnetic fields. Measurements of the operation of such a cavity will be made as functions of external magnetic field and charged particle beam intensity and compared with models to understand the characteristics of this technology and to develop mitigating strategies if necessary.

CHARLES, Ankenbrandt

2009-04-17T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Traveling Wave RF Systems for Helical Cooling Channels  

SciTech Connect (OSTI)

The great advantage of the helical ionization cooling channel (HCC) is its compact structure that enables the fast cooling of muon beam 6-dimensional phase space. This compact aspect requires a high average RF gradient, with few places that do not have cavities. Also, the muon beam is diffuse and requires an RF system with large transverse and longitudinal acceptance. A traveling wave system can address these requirements. First, the number of RF power coupling ports can be significantly reduced compared with our previous pillbox concept. Secondly, by adding a nose on the cell iris, the presence of thin metal foils traversed by the muons can possibly be avoided. We show simulations of the cooling performance of a traveling wave RF system in a HCC, including cavity geometries with inter-cell RF power couplers needed for power propagation.

Yonehara, K.; Lunin, A.; Moretti, A.; Popovic, M.; Romanov, G.; /Fermilab; Neubauer, M.; Johnson, R.P.; /Muons Inc., Batavia; Thorndahl, L.; /CERN

2009-05-01T23:59:59.000Z

302

Ten questions and answers about superconductivity  

E-Print Network [OSTI]

This work answers the basic questions of superconductivity in a question-and-answer format. We extend a basic hypothesis to various superconductors. This hypothesis is that superconductivity requires that the pairing gap locates around the Fermi level. On the basis of this hypothesis our calculations give the so-called three factor theory with which some key problems of the high temperature superconductivity are explained.

Tian De Cao

2012-11-13T23:59:59.000Z

303

Scalable quantum computer using superconducting charge qubits  

E-Print Network [OSTI]

We present a scalable scheme for superconducting charge qubits with the assistance of one-dimensional superconducting transmission line resonator (STLR) playing the role of data bus. The coupling between qubit and data bus may be turned on and off by just controlling the gate voltage and externally applied flux of superconducting charge qubit. In our proposal, the entanglement between arbitrary two qubits and $W$ states of three qubits can be generated quickly and easily.

W. Y. Huo; G. L. Long

2007-06-15T23:59:59.000Z

304

Static forces in a superconducting magnet bearing  

SciTech Connect (OSTI)

Static levitation forces and stiffnesses in a superconducting bearing consisting of concentric ring magnets and a superconducting YBaCuO ring are investigated. In the field-cooled mode a levitation force of 20 N has been achieved. The axial and radial stiffnesses have values of 15 N/mm and 10 N/mm, respectively. An arrangement with two bearings supporting a high speed shaft is now under development. A possible application of superconducting magnetic bearings is flywheels for energy storage.

Stoye, P.; Fuchs, G. [Institut fuer Festkoerper- und Werkstofforschung, Dresden (Germany)] [Institut fuer Festkoerper- und Werkstofforschung, Dresden (Germany); Gawalek, W.; Goernert, P. [Institut fuer Physikalische Hochtechnologie, Jena (Germany)] [Institut fuer Physikalische Hochtechnologie, Jena (Germany); Gladun, A. [Technische Univ., Dresden (Germany)] [Technische Univ., Dresden (Germany)

1995-11-01T23:59:59.000Z

305

Etching of Niobium Sample Placed on Superconducting Radio Frequency Cavity Surface in Ar/CL2 Plasma  

SciTech Connect (OSTI)

Plasma based surface modification is a promising alternative to wet etching of superconducting radio frequency (SRF) cavities. It has been proven with flat samples that the bulk Niobium (Nb) removal rate and the surface roughness after the plasma etchings are equal to or better than wet etching processes. To optimize the plasma parameters, we are using a single cell cavity with 20 sample holders symmetrically distributed over the cell. These holders serve the purpose of diagnostic ports for the measurement of the plasma parameters and for the holding of the Nb sample to be etched. The plasma properties at RF (100 MHz) and MW (2.45 GHz) frequencies are being measured with the help of electrical and optical probes at different pressures and RF power levels inside of this cavity. The niobium coupons placed on several holders around the cell are being etched simultaneously. The etching results will be presented at this conference.

Janardan Upadhyay, Larry Phillips, Anne-Marie Valente

2011-09-01T23:59:59.000Z

306

Relativistic Motion with Superconducting Qubits  

E-Print Network [OSTI]

We show how the dynamical modulation of the qubit-field coupling strength in a circuit quantum electrodynamics architecture mimics the motion of the qubit at relativistic speeds. This allows us to propose a realistic experiment to detect microwave photons coming from simulated acceleration radiation. Moreover, by combining this technique with the dynamical Casimir physics, we enhance the toolbox for studying relativistic phenomena in quantum field theory with superconducting circuits.

Felicetti, S; Fuentes, I; Lamata, L; Romero, G; Solano, E

2015-01-01T23:59:59.000Z

307

Effective theory of color superconductivity  

E-Print Network [OSTI]

We briefly review an effective theory of QCD at high baryon density, describing the relevant modes near the Fermi surface. The high density effective theory has properties of reparametrization invariance and gauge invariance, maintained in a subtle way. It also has a positive measure, allowing lattice simulations at high baryon density. We then apply it to gapless superconductors and discuss recent proposals to resolve the magnetic instability of gapless superconductivity.

Deog Ki Hong

2007-07-17T23:59:59.000Z

308

Wideband high efficiency CMOS envelope amplifiers for 4G LTE handset envelope tracking RF power amplifiers  

E-Print Network [OSTI]

addition, the small equivalent resistance of 8? of the RF PAor inefficient. The equivalent resistance of RF PA, R PA ,normalized equivalent load resistance (R PA ) representing

Hassan, Muhammad

2012-01-01T23:59:59.000Z

309

Superconducting inductive displacement detection of a microcantilever  

SciTech Connect (OSTI)

We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100??T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2?K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

Vinante, A., E-mail: anvinante@fbk.eu [Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento (Italy)

2014-07-21T23:59:59.000Z

310

Superconducting inductive displacement detection of a microcantilever  

E-Print Network [OSTI]

We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100 $\\mu$T, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at $4.2$ K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

Andrea Vinante

2014-05-14T23:59:59.000Z

311

Superconductive articles including cerium oxide layer  

DOE Patents [OSTI]

A ceramic superconductor comprising a metal oxide substrate, a ceramic high temperature superconductive material, and a intermediate layer of a material having a cubic crystal structure, said layer situated between the substrate and the superconductive material is provided, and a structure for supporting a ceramic superconducting material is provided, said structure comprising a metal oxide substrate, and a layer situated over the surface of the substrate to substantially inhibit interdiffusion between the substrate and a ceramic superconducting material deposited upon said structure. 7 figures.

Wu, X.D.; Muenchausen, R.E.

1993-11-16T23:59:59.000Z

312

Reverse circling supercurrents along a superconducting ring  

E-Print Network [OSTI]

The reason why high temperature superconductivity has been being debated is that many basic ideas in literatures are wrong. This work shows that the magnetic flux quantum in a superconducting ring have been inaccurately explained in fact, thus we suggest a reinterpretation of the magnetic flux quantum in a superconducting ring on the basis of the translations of pairs. We also predict that the internal and external surface of a superconducting tube have the reverse circling supercurrents. This means that a more thick tube could trap a larger amount of flux. Both the magnetic flux quantum and the reverse circling supercurrents could not be found with the London equation.

Tian De Cao

2012-01-21T23:59:59.000Z

313

Superconducting Magnet Technology for Future Hadron Colliders  

E-Print Network [OSTI]

Trans. on Applied Superconductivity, 5 (1995), J.R. Millersummer study on superconductingdevices and acceleratorsGeneral. Advanced Superconductors (IGC). Waterbury.

Scanlan, R.M.

2011-01-01T23:59:59.000Z

314

New Advance in SuperConducting Materials  

ScienceCinema (OSTI)

Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laborator...  

None

2010-01-08T23:59:59.000Z

315

Metastable Superconducting Cuprate Phase - Energy Innovation...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Electricity Transmission Find More Like This Return to Search Metastable Superconducting Cuprate Phase Brookhaven National Laboratory Contact BNL About This Technology...

316

Superconducting Cuprates on Catalytic Substrates - Energy Innovation...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Transmission Electricity Transmission Find More Like This Return to Search Superconducting Cuprates on Catalytic Substrates Brookhaven National Laboratory Contact BNL About...

317

High-power RF testing of a 352-MHZ fast-ferrite RF cavity tuner at the Advanced Photon Source.  

SciTech Connect (OSTI)

A 352-MHz fast-ferrite rf cavity tuner, manufactured by Advanced Ferrite Technology, was high-power tested on a single-cell copper rf cavity at the Advanced Photon Source. These tests measured the fast-ferrite tuner performance in terms of power handling capability, tuning bandwidth, tuning speed, stability, and rf losses. The test system comprises a single-cell copper rf cavity fitted with two identical coupling loops, one for input rf power and the other for coupling the fast-ferrite tuner to the cavity fields. The fast-ferrite tuner rf circuit consists of a cavity coupling loop, a 6-1/8-inch EIA coaxial line system with directional couplers, and an adjustable 360{sup o} mechanical phase shifter in series with the fast-ferrite tuner. A bipolar DC bias supply, controlled by a low-level rf cavity tuning loop consisting of an rf phase detector and a PID amplifier, is used to provide a variable bias current to the tuner ferrite material to maintain the test cavity at resonance. Losses in the fast-ferrite tuner are calculated from cooling water calorimetry. Test data will be presented.

Horan, D.; Cherbak, E.; Accelerator Systems Division (APS)

2006-01-01T23:59:59.000Z

318

E-Print Network 3.0 - anisotropic superconducting properties...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in the Superconductivity Group Background|: i) Experiments... in high-magnetic-fields: Members of the superconductivity group in Durham have published arguably the most......

319

Progress on Superconducting Magnets for the MICE Cooling Channel  

E-Print Network [OSTI]

IEEE Transactions on Applied Superconductivty 15, No. 2, p274 Progress on the Superconducting Magnets for the MICETransactions on Applied Superconductivity 13, No. 2 p 1373 (

Green, Michael A

2010-01-01T23:59:59.000Z

320

Magnetism and superconductivity observed to exist in harmony  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Magnetism and superconductivity exist in harmony Magnetism and superconductivity observed to exist in harmony Physicists have observed, for the first time in a single exotic phase,...

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL  

E-Print Network [OSTI]

FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Theand breakage of the superconductor. The UPA circuit melted

Green, M.A.

2010-01-01T23:59:59.000Z

322

Quantum transport and field-induced superconductivity in carbon nanotubes.  

E-Print Network [OSTI]

?? For my thesis, I conducted experiments to investigate superconductivity and superconducting proximity effect in carbon nanotubes. The measurements are carried out on carbon nanotube… (more)

Yang, Yanfei

2010-01-01T23:59:59.000Z

323

Los Alamos scientists see new mechanism for superconductivity  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

superconductivity without phonons LOS ALAMOS, New Mexico, November 24, 2008-Los Alamos National Laboratory researchers have posited an explanation for superconductivity...

324

applied superconductivity conference: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the High Energy Storage Ring (HESR) Index Terms--Antiproton beams, fast-ramped superconduct- ing Ohta, Shigemi 2 Presented at the Applied Superconductivity Conference at...

325

antimatter superconducting spectrometer: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

are described. Hbner, K 2001-01-01 250 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

326

anisotropic superconducting ybco: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

are described. Hbner, K 2001-01-01 368 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

327

aluminium stabilized superconducting: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

are described. Hbner, K 2001-01-01 165 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

328

anu superconducting linac: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

are described. Hbner, K 2001-01-01 367 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

329

argonne superconducting linac: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

are described. Hbner, K 2001-01-01 282 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

330

apt superconducting cavities: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

an example. Klingbeil, H 2011-01-01 147 Synthesising arbitrary quantum states in a superconduct-ing resonator Computer Technologies and Information Sciences Websites Summary:...

331

New Superconducting Magnet Will Lead to Next Generation of Wind...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators New Superconducting Magnet Will Lead to Next Generation of Wind Turbine Generators September 12,...

332

Design and test results of a 600-kW tetrode amplifier for the Superconducting Super Collider  

SciTech Connect (OSTI)

This paper describes the design and testing of a pulsed 600-kW tetrode amplifier that will be used to drive a radiofrequency quadrupole (RFQ) for the Superconducting Super Collider (SSC). Three stages of amplification provide a nominal gain of 77 dB and peak output power of 600 kW. The amplifier is operated at a pulse width of 100 {mu}s and a repetition frequency of 10 Hz. This paper presents the rf design and calculated operating conditions for the amplifier. Details of the electrical design are presented, along with test results.

Rees, D.E.; Brittain, D.L. [Los Alamos National Lab., NM (United States); Grippe, J.M.; Marrufo, O. [Superconducting Super Collider Lab., Dallas, TX (United States)

1993-05-01T23:59:59.000Z

333

Design and test results of a 600-kW tetrode amplifier for the Superconducting Super Collider  

SciTech Connect (OSTI)

This paper describes the design and testing of a pulsed 600-kW tetrode amplifier that will be used to drive a radiofrequency quadrupole (RFQ) for the Superconducting Super Collider (SSC). Three stages of amplification provide a nominal gain of 77 dB and peak output power of 600 kW. The amplifier is operated at a pulse width of 100 [mu]s and a repetition frequency of 10 Hz. This paper presents the rf design and calculated operating conditions for the amplifier. Details of the electrical design are presented, along with test results.

Rees, D.E.; Brittain, D.L. (Los Alamos National Lab., NM (United States)); Grippe, J.M.; Marrufo, O. (Superconducting Super Collider Lab., Dallas, TX (United States))

1993-01-01T23:59:59.000Z

334

Film Deposition, Cryogenic RF Testing and Materials Analysis of a Nb/Cu Single Cell SRF Cavity  

SciTech Connect (OSTI)

In this study, we present preliminary results on using a cathodic-arc-discharge Nb plasma ion source to establish a Nb film-coated single-cell Cu cavity for SRF research. The polycrystalline Cu cavity was fabricated and mirror-surface-finished by a centrifugal barrel polishing (CBP) process at Jefferson Lab. Special pre-coating processes were conducted, in order to create a template-layer for follow-on Nb grain thickening. A sequence of cryogenic RF testing demonstrated that the Nb film does show superconductivity. But the quality factor of this Nb/Cu cavity is low as a result of high residual surface resistance. We are conducting a thorough materials characterization to explore if some microstructural defects or hydrogen impurities, led to such a low quality factor.

Zhao, Xin [JLAB; Geng, Rongli [JLAB; Palczerski, Ari [JLAB; Li, Yongming [Peking

2013-09-01T23:59:59.000Z

335

Interplay of superconductivity, magnetism, and density waves in rare-earth tritellurides and iron-based superconducting materials  

E-Print Network [OSTI]

3. Magnetism in Metals . . . . . . . . . . . . . . . . .IV Superconductivity and Magnetism in Iron-PnictideIII Superconductivity, Magnetism and Charge-Density Waves in

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

336

Design studies for the LCLS 120 Hz RF gun  

SciTech Connect (OSTI)

A preliminary design studies were carried out at Brookhaven National Laboratory for a photocathode RF gun injection system for LCLS 120 Hz operation. The starting point for the design is 50 Hz BNL Gun IV developed by a BNL/KEK/SHI collaboration. The basic parameters of the 120 Hz gun is discussed in this report. The complete photocathode RF gun injection system is described for a 120 Hz operation. The injector system includes photocathode RF gun, emittance compensation solenoid magnet, laser system and laser beam delivery system, and electron beam diagnostics. The basic design parameters, mechanical modification and the performance will be presented in this report.

Wang, X.J.; Babzien, M.; Ben-Zvi, I.; Chang, X.Y.; Pjerov, S.; Woodle, M.

2000-11-01T23:59:59.000Z

337

An RF dosimeter for independent SAR measurement in MRI scanners  

SciTech Connect (OSTI)

Purpose: The monitoring and management of radio frequency (RF) exposure is critical for ensuring magnetic resonance imaging (MRI) safety. Commercial MRI scanners can overestimate specific absorption rates (SAR) and improperly restrict clinical MRI scans or the application of new MRI sequences, while underestimation of SAR can lead to tissue heating and thermal injury. Accurate scanner-independent RF dosimetry is essential for measuring actual exposure when SAR is critical for ensuring regulatory compliance and MRI safety, for establishing RF exposure while evaluating interventional leads and devices, and for routine MRI quality assessment by medical physicists. However, at present there are no scanner-independent SAR dosimeters. Methods: An SAR dosimeter with an RF transducer comprises two orthogonal, rectangular copper loops and a spherical MRI phantom. The transducer is placed in the magnet bore and calibrated to approximate the resistive loading of the scanner's whole-body birdcage RF coil for human subjects in Philips, GE and Siemens 3 tesla (3T) MRI scanners. The transducer loop reactances are adjusted to minimize interference with the transmit RF field (B{sub 1}) at the MRI frequency. Power from the RF transducer is sampled with a high dynamic range power monitor and recorded on a computer. The deposited power is calibrated and tested on eight different MRI scanners. Whole-body absorbed power vs weight and body mass index (BMI) is measured directly on 26 subjects. Results: A single linear calibration curve sufficed for RF dosimetry at 127.8 MHz on three different Philips and three GE 3T MRI scanners. An RF dosimeter operating at 123.2 MHz on two Siemens 3T scanners required a separate transducer and a slightly different calibration curve. Measurement accuracy was ?3%. With the torso landmarked at the xiphoid, human adult whole?body absorbed power varied approximately linearly with patient weight and BMI. This indicates that whole-body torso SAR is on average independent of the imaging subject, albeit with fluctuations. Conclusions: Our 3T RF dosimeter and transducers accurately measure RF exposure in body-equivalent loads and provide scanner-independent assessments of whole-body RF power deposition for establishing safety compliance useful for MRI sequence and device testing.

Qian, Di; Bottomley, Paul A. [Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Maryland 21287 and Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States)] [Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Maryland 21287 and Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); El-Sharkawy, AbdEl-Monem M.; Edelstein, William A., E-mail: w.edelstein@gmail.com [Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Maryland 21287 (United States)

2013-12-15T23:59:59.000Z

338

Cellulose-Bound Magnesium Diboride Superconductivity  

E-Print Network [OSTI]

Cellulose-Bound Magnesium Diboride Superconductivity Y.L. Lin and M.O. Pekguleryuz Department Canada Abstract--Two-phase superconductor tapes were produced by blending high purity magnesium diboride junctions. I. INTRODUCTION Magnesium diboride was found to be superconducting in 2001 by Nagamatsu et al. [1

Ryan, Dominic

339

Quantum logic gates for superconducting resonator qudits  

SciTech Connect (OSTI)

We study quantum information processing using superpositions of Fock states in superconducting resonators as quantum d-level systems (qudits). A universal set of single and coupled logic gates is theoretically proposed for resonators coupled by superconducting circuits of Josephson junctions. These gates use experimentally demonstrated interactions and provide an attractive route to quantum information processing using harmonic oscillator modes.

Strauch, Frederick W. [Williams College, Williamstown, Massachusetts 01267 (United States)

2011-11-15T23:59:59.000Z

340

Superconducting multicell cavity development program at Los Alamos  

SciTech Connect (OSTI)

The superconducting rf (SCRF) cavity Development Program at Los Alamos has designed, fabricated, and tested single-cell niobium cavities at 3-GHz and 805-MHz. This work is being done in preparation for procuring and testing a multicell niobium cavity. The multicell cavity is designed to accelerate protons at [beta] = 0.9; initial tests will be without beam. Progammmatic changes have required us to modify our plans to install a 6800-liter helium cryostat and a 12.8-g/s helium pump. We will use an installed cryostat to test the multicell cavity. Also, the cavity will be modified from a seven-cell to a four-cell structure to match the dimensions of the installed cryostat. Previous reports concentrated on 3-GHz results. In this paper, some of the latest results of the 805-MHz cavity tests are presented. Modifications to allow high pulsed power (HPP) testing on 805-MHz single- and four-cell cavities are proceeding. Glow discharge cleaning of an 805-MHz niobium cavity resulted in a decrease in cavity performance. The cavity was restored to previous performance levels with buffered chemical polishing (bcp). Initial results with high-pressure water cleaning show the process is useful in restoring cavity performance.

Rusnak, B.; Spalek, G.: Gray, E.; DiMarco, J.N.; DeHaven, R.; Novak, J.; Walstrom, P.; Zumbro, J.; Thiessen, H.A. (Los Alamos National Lab., NM (United States)); Langenbrunner, J. (Minnesota Univ., Minneapolis, MN (United States))

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Superconducting multicell cavity development program at Los Alamos  

SciTech Connect (OSTI)

The superconducting rf (SCRF) cavity Development Program at Los Alamos has designed, fabricated, and tested single-cell niobium cavities at 3-GHz and 805-MHz. This work is being done in preparation for procuring and testing a multicell niobium cavity. The multicell cavity is designed to accelerate protons at {beta} = 0.9; initial tests will be without beam. Progammmatic changes have required us to modify our plans to install a 6800-liter helium cryostat and a 12.8-g/s helium pump. We will use an installed cryostat to test the multicell cavity. Also, the cavity will be modified from a seven-cell to a four-cell structure to match the dimensions of the installed cryostat. Previous reports concentrated on 3-GHz results. In this paper, some of the latest results of the 805-MHz cavity tests are presented. Modifications to allow high pulsed power (HPP) testing on 805-MHz single- and four-cell cavities are proceeding. Glow discharge cleaning of an 805-MHz niobium cavity resulted in a decrease in cavity performance. The cavity was restored to previous performance levels with buffered chemical polishing (bcp). Initial results with high-pressure water cleaning show the process is useful in restoring cavity performance.

Rusnak, B.; Spalek, G.: Gray, E.; DiMarco, J.N.; DeHaven, R.; Novak, J.; Walstrom, P.; Zumbro, J.; Thiessen, H.A. [Los Alamos National Lab., NM (United States); Langenbrunner, J. [Minnesota Univ., Minneapolis, MN (United States)

1993-06-01T23:59:59.000Z

342

Three-cell traveling wave superconducting test structure  

SciTech Connect (OSTI)

Use of a superconducting traveling wave accelerating (STWA) structure with a small phase advance per cell rather than a standing wave structure may provide a significant increase of the accelerating gradient in the ILC linac. For the same surface electric and magnetic fields the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing wave cavities. The STWA allows also longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed, manufactured and successfully tested demonstrating the possibility of a proper processing to achieve a high accelerating gradient. These results open way to take the next step of the TW SC cavity development: to build and test a travelingwave three-cell cavity with a feedback waveguide. The latest results of the single-cell cavity tests are discussed as well as the design of the test 3-cell TW cavity.

Avrakhov, Pavel; Kanareykin, Alexei; /Euclid Techlabs, Solon; Kazakov, Sergey; Solyak, Nikolay; Wu, Genfa; Yakovlev, Vyacheslav P.; /Fermilab

2011-03-01T23:59:59.000Z

343

Three-cell traveling wave superconducting test structure  

E-Print Network [OSTI]

Use of a superconducting traveling wave accelerating (STWA) structure with a small phase advance per cell rather than a standing wave structure may provide a significant increase of the accelerating gradient in the ILC linac. For the same surface electric and magnetic fields the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing wave cavities. The STWA allows also longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed, manufactured and successfully tested demonstrating the possibility of a proper processing to achieve a high accelerating gradient. These results open way to take the next step of the TW SC cavity development: to build and test a traveling-wave three-cell cavity with a feedback waveguide. The latest results of the single-cell cavity tests...

Avrakhov, Pavel; Kazakov, Sergey; Solyak, Nikolay; Wu, Genfa; Yakovlev, Vyacheslav P

2011-01-01T23:59:59.000Z

344

Molybdenum-rhenium superconducting suspended nanostructures  

SciTech Connect (OSTI)

Suspended superconducting nanostructures of MoRe 50%/50% by weight are fabricated employing commonly used fabrication steps in micro- and nano-meter scale devices followed by wet-etching with Hydro-fluoric acid of a SiO{sub 2} sacrificial layer. Suspended superconducting channels as narrow as 50?nm and length 3??m have a critical temperature of ?6.5?K, which can increase by 0.5?K upon annealing at 400?°C. A detailed study of the dependence of the superconducting critical current and critical temperature upon annealing and in devices with different channel widths reveals that desorption of contaminants is responsible for the improved superconducting properties. These findings pave the way for the development of superconducting electromechanical devices using standard fabrication techniques.

Aziz, Mohsin; Christopher Hudson, David; Russo, Saverio [Centre for Graphene Science, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom)

2014-06-09T23:59:59.000Z

345

Free-standing oxide superconducting articles  

DOE Patents [OSTI]

A substrate-free, free-standing epitaxially oriented superconductive film including a layer of a template material and a layer of a ceramic superconducting material is provided together with a method of making such a substrate-free ceramic superconductive film by coating an etchable material with a template layer, coating the template layer with a layer of a ceramic superconductive material, coating the layer of ceramic superconductive material with a protective material, removing the etchable material by an appropriate means so that the etchable material is separated from a composite structure including the template lay This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).

Wu, Xin D. (Greenbelt, MD); Muenchausen, Ross E. (Espanola, NM)

1993-01-01T23:59:59.000Z

346

Microelectronic superconducting crossover and coil  

DOE Patents [OSTI]

A microelectronic component comprising a crossover is provided comprising a substrate, a first high T[sub c] superconductor thin film, a second insulating thin film comprising SrTiO[sub 3]; and a third high T[sub c] superconducting film which has strips which crossover one or more areas of the first superconductor film. An in situ method for depositing all three films on a substrate is provided which does not require annealing steps and which can be opened to the atmosphere between depositions. 13 figures.

Wellstood, F.C.; Kingston, J.J.; Clarke, J.

1994-03-01T23:59:59.000Z

347

Fermionic Models with Superconducting Circuits  

E-Print Network [OSTI]

We propose a method for the efficient quantum simulation of fermionic systems with superconducting circuits. It consists in the suitable use of Jordan-Wigner mapping, Trotter decomposition, and multiqubit gates, be with the use of a quantum bus or direct capacitive couplings. We apply our method to the paradigmatic cases of 1D and 2D Fermi-Hubbard models, involving couplings with nearest and next-nearest neighbours. Furthermore, we propose an optimal architecture for this model and discuss the benchmarking of the simulations in realistic circuit quantum electrodynamics setups.

U. Las Heras; L. García-Álvarez; A. Mezzacapo; E. Solano; L. Lamata

2014-11-10T23:59:59.000Z

348

Fermionic Models with Superconducting Circuits  

E-Print Network [OSTI]

We propose a method for the efficient quantum simulation of fermionic systems with superconducting circuits. It consists in the suitable use of Jordan-Wigner mapping, Trotter decomposition, and multiqubit gates, be with the use of a quantum bus or direct capacitive couplings. We apply our method to the paradigmatic cases of 1D and 2D Fermi-Hubbard models, involving couplings with nearest and next-nearest neighbours. Furthermore, we propose an optimal architecture for this model and discuss the benchmarking of the simulations in realistic circuit quantum electrodynamics setups.

U. Las Heras; L. García-Álvarez; A. Mezzacapo; E. Solano; L. Lamata

2015-03-31T23:59:59.000Z

349

Microelectronic superconducting crossover and coil  

DOE Patents [OSTI]

A microelectronic component comprising a crossover is provided comprising a substrate, a first high T.sub.c superconductor thin film, a second insulating thin film comprising SrTiO.sub.3 ; and a third high T.sub.c superconducting film which has strips which crossover one or more areas of the first superconductor film. An in situ method for depositing all three films on a substrate is provided which does not require annealing steps and which can be opened to the atmosphere between depositions.

Wellstood, Frederick C. (Berkeley, CA); Kingston, John J. (Oakland, CA); Clarke, John (Berkeley, CA)

1994-01-01T23:59:59.000Z

350

High performance RF and baseband building blocks for wireless receivers  

E-Print Network [OSTI]

market has suddenly expanded to unimaginable dimensions. Devices such as pagers, cellular and cordless phones, cable modems, and RF identification (RFID) tags are rapidly penetrating all aspects of our lives, evolving from luxury items to indispensable...

Bahmani, Faramarz

2007-09-17T23:59:59.000Z

351

CMOS RF Power Amplifier Design for Wireless Communications  

E-Print Network [OSTI]

conjugate (S22) match (solid curve) and power match (dashedSupply Linear RF Power Amplifier", IEEE J. Solid-State Circ.Fully-integrated CMOS Power Amplifiers", IEEE J. Solid-State

FANG, Qiang

2012-01-01T23:59:59.000Z

352

Progress on the Mice 201 MNz RF Cavity at LBNL  

E-Print Network [OSTI]

like to thank people at LBNL EH&S and Main Machine Shop forMICE 201 MHz RF CAVITY AT LBNL* Tianhuan Luol, Don Summers,Virostek, Michael Zisman, LBNL, Berkeley, CA 94720, USA

Luo, Tianhuan

2014-01-01T23:59:59.000Z

353

Electrodeless lighting RF power source development. Final report  

SciTech Connect (OSTI)

An efficient, solid state RF power source has been developed on this NICE project for exciting low power electrodeless lamp bulbs. This project takes full advantage of concurrent advances in electrodeless lamp technology. Electrodeless lamp lighting systems utilizing the sulfur based bulb type developed by Fusion Lighting, Inc., is an emerging technology which is based on generating light in a confined plasma created and sustained by RF excitation. The bulb for such a lamp is filled with a particular element and inert gas at low pressure when cold. RF power from the RF source creates a plasma within the bulb which reaches temperatures approaching those of high pressure discharge lamp plasmas. At these temperatures the plasma radiates substantial visible light with a spectrum similar to sunlight.

NONE

1996-08-30T23:59:59.000Z

354

Recent Progress of RF Cavity Study at Mucool Test Area  

SciTech Connect (OSTI)

Summar of presentation is: (1) MTA is a multi task working space to investigate RF cavities for R&D of muon beam cooling channel - (a) Intense 400 MeV H{sup -} beam, (b) Handle hydrogen (flammable) gas, (c) 5 Tesla SC solenoid magnet, (d) He cryogenic/recycling system; (2) Pillbox cavity has been refurbished to search better RF material - Beryllium button test will be happened soon; (3) E x B effect has been tested in a box cavity - Under study (result seems not to be desirable); (4) 201 MHz RF cavity with SRF cavity treatment has been tested at low magnetic field - (a) Observed some B field effect on maximum field gradient and (b) Further study is needed (large bore SC magnet will be delivered end of 2011); and (5) HPRF cavity beam test has started - (a) No RF breakdown observed and (b) Design a new HPRF cavity to investigate more plasma loading effect.

Yonehara, Katsuya; /Fermilab

2011-12-02T23:59:59.000Z

355

DESIGN OF A DC/RF PHOTOELECTRON GUN.  

SciTech Connect (OSTI)

An integrated dc/rf photoelectron gun produces a low-emittance beam by first rapidly accelerating electrons at a high gradient during a short ({approx}1 ns), high-voltage pulse, and then injecting the electrons into an rf cavity for subsequent acceleration. Simulations show that significant improvement of the emittance appears when a high field ({approx} 0.5-1 GV/m) is applied to the cathode surface. An adjustable dc gap ({le} 1 mm) which can be integrated with an rf cavity is designed for initial testing at the Injector Test Stand at Argonne National Laboratory using an existing 70-kV pulse generator. Plans for additional experiments of an integrated dc/rf gun with a 250-kV pulse generator are being made.

YU,D.NEWSHAM,Y.SMIRONOV,A.YU,J.SMEDLEY,J.SRINIVASAN RAU,T.LEWELLEN,J.ZHOLENTS,A.

2003-05-12T23:59:59.000Z

356

BN/Graphene/BN Transistors for RF Applications  

E-Print Network [OSTI]

In this letter, we demonstrate the first BN/graphene/BN field-effect transistor for RF applications. This device structure can preserve the high mobility and the high carrier velocity of graphene, even when it is sandwiched ...

Taychatanapat, Thiti

357

Test estructural i predictiu per a circuits RF CMOS.  

E-Print Network [OSTI]

??En aquesta tesi s'ha desenvolupat una tècnica de test que permet testar un LNA i un mesclador, situats en el capçal RF d'un receptor CMOS,… (more)

Suenaga Portugués, Kay

2008-01-01T23:59:59.000Z

358

Spectral measurement of the thermal excitation of a superconducting qubit  

E-Print Network [OSTI]

Spectral measurement of the thermal excitation of a superconducting qubit A. Palacios-Laloy, F of a superconducting qubit 2 Superconducting qubits [1] are promising candidates for implementing a solid- state lying in their ground state. In most superconducting qubit experiments, the initialization is simply

Boyer, Edmond

359

REVIEW OF SUPERCONDUCTING MAGNETOMETERS AND CRYOGENIC REFRIGERATION TECHNIQUES  

E-Print Network [OSTI]

3. REVIEW OF SUPERCONDUCTING MAGNETOMETERS AND CRYOGENIC REFRIGERATION TECHNIQUES By W. S. GOREE of the macroscopic quantum nature of the superconducting state. Several of these properties have direct application a closed superconducting path must remain constant as long as the path remains superconducting

Boyer, Edmond

360

Superconducting coil and method of stress management in a superconducting coil  

DOE Patents [OSTI]

A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

McIntyre, Peter M. (College Station, TX); Shen, Weijun (Oak Ridge, TN); Diaczenko, Nick (College Station, TX); Gross, Dan A. (College Station, TX)

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Measurement of current distribution on RF coils using MR imaging  

E-Print Network [OSTI]

MEASUREMENT OF CURRENT DISTRIBUTION ON RF COILS USING MR IMAGING A Thesis by YU WU Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December... 1993 Major Subject' Electrical Engineering MEASUREMENT OF CURRENT DISTRIBUTION ON RF COILS USING MR IMAGING A Thesis by YU WU Submitted to Texas ASM University in partial fulfillment of the requirments for the degree of MASTER OF SCIENCE...

Wu, Yu

1993-01-01T23:59:59.000Z

362

RF-MEMS Switched Varactors for Medium Power Applications  

E-Print Network [OSTI]

In RF (Radio Frequency) domain, one of the limitations of using MEMS (Micro Electromechanical Systems) switching devices for medium power applications is RF power. Failure phenomena appear even for 500 mW. A design of MEMS switched capacitors with an enhanced topology is presented in this paper to prevent it. This kind of device and its promising performances will serve to fabricate a MEMS based phase shifter able to work under several watts.

Maury, F; Crunteanu, A; Conseil, F; Blondy, P

2008-01-01T23:59:59.000Z

363

High Temperature Superconducting Underground Cable  

SciTech Connect (OSTI)

The purpose of this Project was to design, build, install and demonstrate the technical feasibility of an underground high temperature superconducting (HTS) power cable installed between two utility substations. In the first phase two HTS cables, 320 m and 30 m in length, were constructed using 1st generation BSCCO wire. The two 34.5 kV, 800 Arms, 48 MVA sections were connected together using a superconducting joint in an underground vault. In the second phase the 30 m BSCCO cable was replaced by one constructed with 2nd generation YBCO wire. 2nd generation wire is needed for commercialization because of inherent cost and performance benefits. Primary objectives of the Project were to build and operate an HTS cable system which demonstrates significant progress towards commercial progress and addresses real world utility concerns such as installation, maintenance, reliability and compatibility with the existing grid. Four key technical areas addressed were the HTS cable and terminations (where the cable connects to the grid), cryogenic refrigeration system, underground cable-to-cable joint (needed for replacement of cable sections) and cost-effective 2nd generation HTS wire. This was the world’s first installation and operation of an HTS cable underground, between two utility substations as well as the first to demonstrate a cable-to-cable joint, remote monitoring system and 2nd generation HTS.

Farrell, Roger, A.

2010-02-28T23:59:59.000Z

364

Wakefield and RF Kicks Due to Coupler Asymmetry in TESLA-Type Accelerating Cavities  

SciTech Connect (OSTI)

In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and higher mode (HM) couplers that are asymmetric and thus the source of such kicks. The kicks are of two types: one, due to (the asymmetry in) the fundamental RF fields and the other, due to transverse wakefields that are generated by the beam even when it is on axis. In this report we calculate the strength of these kicks and estimate their effect on the ILC beam. The TESLA cavity comprises nine cells, one HM coupler in the upstream end, and one (identical, though rotated) HM coupler and one FM coupler in the downstream end (for their shapes and location see Figs. 1, 2) [1]. The cavity is 1.1 m long, the iris radius 35 mm, and the coupler beam pipe radius 39 mm. Note that the couplers reach closer to the axis than the irises, down to a distance of 30 mm.

Bane, K.L.F.; Adolphsen, C.; Li, Z.; /SLAC; Dohlus, M.; Zagorodnov, I.; /DESY; Gonin, I.; Lunin, A.; Solyak, N.; Yakovlev, V.; /Fermilab; Gjonaj, E.; Weiland, T.; /Darmstadt, Tech. Hochsch.

2008-07-07T23:59:59.000Z

365

Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization  

E-Print Network [OSTI]

4.3.2 Superconducting microstrip simulations 4.4 Impedance4.3 Superconducting microstrip . . . . . . . . . . 4.3.1Principles of superconductive devices and circuits, (second

Myers, Michael James

2010-01-01T23:59:59.000Z

366

Optimization of superconducting flux qubit readout using near-quantum-limited amplifiers  

E-Print Network [OSTI]

junctions . . . . . . . 1.4 Superconducting QuantumInterference 1.5 Superconducting qubits . . . . . . . . .2 Superconducting flux qubits 2.1 The one-junction flux

Johnson, Jedediah Edward Jensen

2012-01-01T23:59:59.000Z

367

A Superconducting Bending Magnet System for a Compact Synchrotron Light Source  

E-Print Network [OSTI]

Garren, "Optimization of Superconducting Bending Magnets foral, "Development of a Superconducting Compact Storage Ringsdesigns M. A Green, "Superconducting Dipole Magnets for

Green, M.A.

2011-01-01T23:59:59.000Z

368

A SUPERCONDUCTING MAGNET SYSTEM FOR THE SPIRIT COSMIC RAY SPACE TELESCOPE  

E-Print Network [OSTI]

secondary circuit*® NbVSh superconducting coils ElectricalAugust 21-24, 1979 A SUPERCONDUCTING MAGNET SYSTEM FOR THETELESCOPE MASTER A SUPERCONDUCTING MAGNET SYSTEM FOR THE

Green, M.A.

2010-01-01T23:59:59.000Z

369

Fabrication of superconducting nanowire single proton detectors  

E-Print Network [OSTI]

The future NASA Mars project will need an ultra-fast, highly sensitive photodetector to increase the bandwidth of free-space long-range communication, which is now done primarily using RF signals. Our original motivation ...

Yang, Joel K. (Joel Kwang wei)

2005-01-01T23:59:59.000Z

370

Superconducting surface impedance under radiofrequency field  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Based on BCS theory with moving Cooper pairs, the electron states distribution at 0K and the probability of electron occupation with finite temperature have been derived and applied to anomalous skin effect theory to obtain the surface impedance of a superconductor under radiofrequency (RF) field. We present the numerical results for Nb and compare these with representative RF field-dependent effective surface resistance measurements from a 1.5 GHz resonant structure.

Xiao, Binping [JLAB, William and Mary College; Reece, Charles E. [JLAB; Kelley, Michael J. [JLAB, William and Mary College

2013-07-01T23:59:59.000Z

371

Nanostructural features affecting superconducting radio frequency niobium cavities revealed using TEM and EELS  

E-Print Network [OSTI]

Nanoscale defect structure within the magnetic penetration depth of ~100nm is key to the performance limitations of niobium superconducting radio frequency (SRF) cavities. Using a unique combination of advanced thermometry during cavity RF measurements, and TEM structural and compositional characterization of the samples extracted from cavity walls, we discover the existence of nanoscale hydrides in electropolished cavities limited by the high field Q slope, and show the decreased hydride formation in the electropolished cavity after 120C baking. Furthermore, we demonstrate that adding 800C hydrogen degassing followed by light buffered chemical polishing restores the hydride formation to the pre-120C bake level. We also show absence of niobium oxides along the grain boundaries and the modifications of the surface oxide upon 120C bake.

Trenikhina, Y; Kwon, J; Zuo, J -M; Zasadzinski, J F

2015-01-01T23:59:59.000Z

372

Superconductivity  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

REU participants PAGE 27 Volume 18 No. 1 * Spring 2011 Sweet Success: Ten years of hybrid magnet research PAGE 7 Ten years of hybrid magnet research PAGE 7 TABLE OF CONTENTS 7...

373

RF-Plasma Source Commissioning in Indian Negative Ion Facility  

SciTech Connect (OSTI)

The Indian program of the RF based negative ion source has started off with the commissioning of ROBIN, the inductively coupled RF based negative ion source facility under establishment at Institute for Plasma research (IPR), India. The facility is being developed under a technology transfer agreement with IPP Garching. It consists of a single RF driver based beam source (BATMAN replica) coupled to a 100 kW, 1 MHz RF generator with a self excited oscillator, through a matching network, for plasma production and ion extraction and acceleration. The delivery of the RF generator and the RF plasma source without the accelerator, has enabled initiation of plasma production experiments. The recent experimental campaign has established the matching circuit parameters that result in plasma production with density in the range of 0.5-1x10{sup 18}/m{sup 3}, at operational gas pressures ranging between 0.4-1 Pa. Various configurations of the matching network have been experimented upon to obtain a stable operation of the set up for RF powers ranging between 25-85 kW and pulse lengths ranging between 4-20 s. It has been observed that the range of the parameters of the matching circuit, over which the frequency of the power supply is stable, is narrow and further experiments with increased number of turns in the coil are in the pipeline to see if the range can be widened. In this paper, the description of the experimental system and the commissioning data related to the optimisation of the various parameters of the matching network, to obtain stable plasma of required density, are presented and discussed.

Singh, M. J.; Bandyopadhyay, M.; Yadava, Ratnakar; Chakraborty, A. K. [ITER- India, Institute for Plasma Research, A-29, Sector 25, GIDC, Gandhinagar, Gujrat (India); Bansal, G.; Gahlaut, A.; Soni, J.; Kumar, Sunil; Pandya, K.; Parmar, K. G.; Sonara, J. [Institute for Plasma Research, Bhat Gandhinagar, Gujrat (India); Kraus, W.; Heinemann, B.; Riedl, R.; Obermayer, S.; Martens, C.; Franzen, P.; Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

2011-09-26T23:59:59.000Z

374

Gapless superconductivity and string theory  

E-Print Network [OSTI]

Coexistence of superconducting and normal components in nanowires at currents below the critical (a "mixed" state) would have important consequences for the nature and range of potential applications of these systems. For clean samples, it represents a genuine interaction effect, not seen in the mean-field theory. Here we consider properties of such a state in the gravity dual of a strongly coupled superconductor constructed from D3 and D5 branes. We find numerically uniform gapless solutions containing both components but argue that they are unstable against phase separation, as their free energies are not convex. We speculate on the possible nature of the resulting non-uniform sate ("emulsion") and draw analogies between that state and the familiar mixed state of a type II superconductor in a magnetic field.

Sergei Khlebnikov

2014-11-06T23:59:59.000Z

375

Crossovers between superconducting symmetry classes  

E-Print Network [OSTI]

We study the average density of states in a small metallic grain coupled to two superconductors with the phase difference $\\pi$, in a magnetic field. The spectrum of the low-energy excitations in the grain is described by the random matrix theory whose symmetry depends on the magnetic field strength and coupling to the superconductors. In the limiting cases, a pure superconducting symmetry class is realized. For intermediate magnetic fields or couplings to the superconductors, the system experiences a crossover between different symmetry classes. With the help of the supersymmetric sigma-model we derive the exact expressions for the average density of states in the crossovers between the symmetry classes A-C and CI-C.

V. A. Koziy; M. A. Skvortsov

2011-06-20T23:59:59.000Z

376

Subranging technique using superconducting technology  

DOE Patents [OSTI]

Subranging techniques using "digital SQUIDs" are used to design systems with large dynamic range, high resolution and large bandwidth. Analog-to-digital converters (ADCs) embodying the invention include a first SQUID based "coarse" resolution circuit and a second SQUID based "fine" resolution circuit to convert an analog input signal into "coarse" and "fine" digital signals for subsequent processing. In one embodiment, an ADC includes circuitry for supplying an analog input signal to an input coil having at least a first inductive section and a second inductive section. A first superconducting quantum interference device (SQUID) is coupled to the first inductive section and a second SQUID is coupled to the second inductive section. The first SQUID is designed to produce "coarse" (large amplitude, low resolution) output signals and the second SQUID is designed to produce "fine" (low amplitude, high resolution) output signals in response to the analog input signals.

Gupta, Deepnarayan (Hawthorne, NY)

2003-01-01T23:59:59.000Z

377

Superconductivity for electric power systems: Program overview  

SciTech Connect (OSTI)

Largely due to government and private industry partnerships, electric power applications based upon high-temperature superconductivity are now being designed and tested only seven years after the discovery of the high-temperature superconductors. These applications offer many benefits to the national electric system including: increased energy efficiency, reduced equipment size, reduced emissions, increased stability/reliability, deferred expansion, and flexible electricity dispatch/load management. All of these benefits have a common outcome: lower electricity costs and improved environmental quality. The U.S. Department of Energy (DOE) sponsors research and development through its Superconductivity Program for Electric Power Systems. This program will help develop the technology needed for U.S. industries to commercialize high-temperature superconductive electric power applications. DOE envisions that by 2010 the U.S. electric power systems equipment industry will regain a major share of the global market by offering superconducting products that outperform the competition.

Not Available

1995-02-01T23:59:59.000Z

378

Near-zero modes in superconducting graphene  

E-Print Network [OSTI]

Vortices in the simplest superconducting state of graphene contain very-low-energy excitations whose existence is connected to an index theorem that applies strictly to an approximate form of the relevant Bogoliubov–de ...

Ghaemi, Pouyan

379

Cooling arrangement for a superconducting coil  

DOE Patents [OSTI]

A superconducting device is disclosed, such as a superconducting rotor for a generator or motor. A vacuum enclosure has an interior wall surrounding a cavity containing a vacuum. A superconductive coil is placed in the cavity. A generally-annularly-arranged, thermally-conductive sheet has an inward-facing surface contacting generally the entire outward-facing surface of the superconductive coil. A generally-annularly-arranged coolant tube contains a cryogenic fluid and contacts a generally-circumferential portion of the outward-facing surface of the sheet. A generally-annularly-arranged, thermally-insulative coil overwrap generally circumferentially surrounds the sheet. The coolant tube and the inward-facing surface of the coil overwrap together contact generally the entire outward-facing surface of the sheet. 3 figs.

Herd, K.G.; Laskaris, E.T.

1998-06-30T23:59:59.000Z

380

Operational experience with superconducting synchrotron magnets  

SciTech Connect (OSTI)

The operational experience with the Fermilab Tevatron is presented, with emphasis on reliability and failure modes. Comprisons are made between the operating efficiencies for the superconducting machine and for he conventional Main Ring.

Martin, P.S.

1987-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Coupling light to superconductive photon counters  

E-Print Network [OSTI]

Superconductive nanowire single-photon detectors (SNSPDs) are an emerging, ultrasensitive photon counting technology which may enable fiber-based, long-haul quantum key distribution. Our group has successfully developed a ...

Hu, Xiaolong

2008-01-01T23:59:59.000Z

382

New Advances in SuperConducting Materials  

ScienceCinema (OSTI)

Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laboratory, new materials science concepts are bringing this essential technology closer to widespread industrial use.

None

2014-08-12T23:59:59.000Z

383

Armored spring-core superconducting cable and method of construction  

DOE Patents [OSTI]

An armored spring-core superconducting cable (12) is provided. The armored spring-core superconducting cable (12) may include a spring-core (20), at least one superconducting strand (24) wound onto the spring-core (20), and an armored shell (22) that encases the superconducting strands (24). The spring-core (20) is generally a perforated tube that allows purge gases and cryogenic liquids to be circulated through the armored superconducting cable (12), as well as managing the internal stresses within the armored spring-core superconducting cable (12). The armored shell (22) manages the external stresses of the armored spring-core superconducting cable (12) to protect the fragile superconducting strands (24). The armored spring-core superconducting cable (12) may also include a conductive jacket (34) formed outwardly of the armored shell (22).

McIntyre, Peter M. (611 Montclair, College Station, TX 77840); Soika, Rainer H. (1 Hensel, #X4C, College Station, TX 77840)

2002-01-01T23:59:59.000Z

384

Architecture for high critical current superconducting tapes  

DOE Patents [OSTI]

Improvements in critical current capacity for superconducting film structures are disclosed and include the use of, e.g., multilayer YBCO structures where individual YBCO layers are separated by a layer of an insulating material such as CeO.sub.2 and the like, a layer of a conducting material such as strontium ruthenium oxide and the like or by a second superconducting material such as SmBCO and the like.

Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

2002-01-01T23:59:59.000Z

385

A superconducting dipole magnet for laser spectroscopy  

E-Print Network [OSTI]

A SUPERCONDUCTING DIPOLE MAGNET FOR LASER SPECTROSCOPY A Thesis by KENNETH EDWARD WAGENHAUSER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requhements for the degree of MASTER OF SCIENCE... May 1990 Major subject: Physics A SUPERCONDUCTING DIPOLE MAGNET FOR LASER SPECTROSCOPY A thesis by KENNETH EDWARD WAGENHAUSER Approved to as to style and content by: Hans A. Schuessler (Chair of Committee) David H. Russell (Member) Glenn A...

Wagenhauser, Kenneth Edward

1990-01-01T23:59:59.000Z

386

Electromagnetic Modelling of Superconducting Sensor Designs  

E-Print Network [OSTI]

transition temperature) the superconductive property of the metal disappears, and the metal behaves as a normal resistive material. Another basic feature of superconductors is the Meissner effect: magnetic flux cannot penetrate a metal in its... superconductive state apart from a very small region near the surface, where all the induced current is concentrated. If a magnetic field is applied and then the temperature decreased below Tc, flux is expelled from the bulk; if the superconductor is in the form...

Gerra, Guido

387

Scalable Superconducting Architecture for Adiabatic Quantum Computation  

E-Print Network [OSTI]

A scalable superconducting architecture for adiabatic quantum computers is proposed. The architecture is based on time-independent, nearest-neighbor interqubit couplings: it can handle any problem in the class NP even in the presence of measurement errors, noise, and decoherence. The implementation of this architecture with superconducting persistent-current qubits and the natural robustness of such an implementation to manufacturing imprecision and decoherence are discussed.

William M. Kaminsky; Seth Lloyd; Terry P. Orlando

2004-03-12T23:59:59.000Z

388

Lattice Vibrations and Superconductivity in Layered Structures  

E-Print Network [OSTI]

PHYSICAL REVIEW B VOLUME 2, NUMBER 7 1 OCTOB ER, 1970 Lattice Vibrations and Superconductivity in Layered Structures* B. E. Allen, G. P. Alldredge, and F. W. de bette DePartment of Physics, University of Texas, Austin, Texas 78712 (Received 18... May 1970) In order to estimate the influence of both surface and interface effects on phonon frequencies and superconducting transition temperatures in layered structures, we have calculated the vibrational modes of structures composed...

Allen, Roland E.; Alldredg, GP; WETTE, FWD.

1970-01-01T23:59:59.000Z

389

Nanofabrication | Center for Functional Nanomaterials  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohn F. Geisz,AerialStaff NUGWedged Crater.

390

Phase Stable RF-over-fiber Transmission using Heterodyne Interferometry  

SciTech Connect (OSTI)

New scientific applications require phase-stabilized RF distribution to multiple remote locations. These include phased-array radio telescopes and short pulse free electron lasers. RF modulated onto a CW optical carrier and transmitted via fiber is capable of low noise, but commercially available systems aren't long term stable enough for these applications. Typical requirements are for less than 50fs long term temporal stability between receivers, which is 0.05 degrees at 3GHz. Good results have been demonstrated for RF distribution schemes based on transmission of short pulses, but these require specialized free-space optics and high stability mechanical infrastructure. We report a method which uses only standard telecom optical and RF components, and achieves less than 20fs RMS error over 300m of standard single-mode fiber. We demonstrate stable transmission of 3GHz over 300m of fiber with less than 0.017 degree (17fs) RMS phase error. An interferometer measures optical phase delay, providing information to a feed-forward correction of RF phase.

Wilcox, R.; Byrd, J. M.; Doolittle, L.; Huang, G.; Staples, J. W.

2010-01-02T23:59:59.000Z

391

RF Power Upgrade for CEBAF at Jefferson Laboratory  

SciTech Connect (OSTI)

Jefferson Laboratory (JLab) is currently upgrading the 6GeV Continuous Electron Beam Accelerator Facility (CEBAF) to 12GeV. As part of the upgrade, RF systems will be added, bringing the total from 340 to 420. Existing RF systems can provide up to 6.5 kW of CW RF at 1497 MHZ. The 80 new systems will provide increased RF power of up to 13 kW CW each. Built around a newly designed and higher efficiency 13 kW klystron developed for JLab by L-3 Communications, each new RF chain is a completely revamped system using hardware different than our present installations. This paper will discuss the main components of the new systems including the 13 kW klystron, waveguide isolator, and HV power supply using switch-mode technology. Methodology for selection of the various components and results of initial testing will also be addressed. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

Andrew Kimber,Richard Nelson

2011-03-01T23:59:59.000Z

392

RF Pulse compression stabilization at the CTF3 CLIC test facility  

E-Print Network [OSTI]

In the CTF3 accelerator, the RF produced by each of ten 3 GHz klystrons goes through waveguides, RF pulse compressors and splitters. The RF phase and power transformation of these devices depend on their temperature. The quantitative effect of the room temperature variation on the RF was measured. It is the major source of undesired changes during the CTF3 operation. An RF phaseloop and a compressor temperature stabilization are developed to suppress the phase fluctuation and the power profile change due to the temperature variation. The implementation is transparent for operators, it does not limit anyhow the flexibility of RF manipulations. Expected and measured suppression characteristics will be given.

Dubrovskiy, Alexey

2010-01-01T23:59:59.000Z

393

Entangling two superconducting LC coherent modes via a superconducting flux qubit  

E-Print Network [OSTI]

Based on a pure solid-state device consisting of two superconducting LC circuits coupled to a superconducting flux qubit, we propose in this paper that the maximally entangled coherent states of the two LC modes can be generated for arbitrary coherent states through flux qubit controls.

Mei-Yu Chen; Matisse W. Y. Tu; Wei-Min Zhang

2009-11-10T23:59:59.000Z

394

The superconducting spin valve and triplet superconductivity I.A. Garifullin a,n  

E-Print Network [OSTI]

The superconducting spin valve and triplet superconductivity I.A. Garifullin a,n , P.V. Leksin s t r a c t A review of our recent results on the spin valve effect is presented. We have used coefficient DF and the exchange splitting I of the conduction band in the F layer [1]. For pure Fe the value

Fominov, Yakov

395

R & D on Very-High-Current Superconducting Proton Linac, Final Report  

SciTech Connect (OSTI)

The aim of this R&D project was to develop a superconducting cavity for a very-­? high-­?current proton accelerator. The particular application motivating the proposal was a LHC upgrade called the Superconducting Proton Linac, or SPL. Under the grant awarded to Stony Brook University the cavity was designed, a prototype copper cavity, followed by the niobium cavity, were built. A new set of HOM dampers was developed. The cavity has outstanding RF performance parameters – low surface fields, low power loss and all HOMs are fully damped. In fact, it is a “universal cavity” in the sense that it is suited for the acceleration of high-­?current protons and well as high current electrons. Its damping of HOM modes is so good that it can see service in a multi-­?pass linac or an Energy Recovery Linac in addition to the easier service in a single-­?pass linac. Extensive measurements were made on the cavities and couplers, with the exception of the cold test of the niobium cavity. At the time of this report the cavity has been chemically processed and is ready for vertical testing which will be carried out shortly.

Ben-Zvi, Ilan

2013-03-31T23:59:59.000Z

396

Integrated Surface Topography Characterization of Variously Polished Niobium for Superconducting Particle Accelerators  

SciTech Connect (OSTI)

As superconducting niobium radio-frequency (SRF) cavities approach fundamental material limits, there is increased interest in understanding the details of topographical influences on realized performance limitations. Micro-and nano-roughness are implicated in both direct geometrical field enhancements as well as complications of the composition of the 50 nm surface layer in which the super-currents flow. Interior surface chemical polishing (BCP/EP) to remove mechanical damage leaves surface topography, including pits and protrusions of varying sharpness. These may promote RF magnetic field entry, locally quenching superconductivity, so as to degrade cavity performance. A more incisive analysis of surface topography than the widely-used average roughness is needed. In this study, a power spectral density (PSD) approach based on Fourier analysis of surface topography data acquired by both stylus profilometry and atomic force microscopy (AFM) is being used to distinguish the scale-dependent smoothing effects. The topographical evolution of the Nb surface as a function of different steps of EP is reported, resulting in a novel qualitative and quantitative description of Nb surface topography.

Hui Tian, Charles Reece, Michael Kelley, G. Ribeill

2009-05-01T23:59:59.000Z

397

A computer program for HVDC converter station RF noise calculations  

SciTech Connect (OSTI)

HVDC converter station operations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. A generic Radio Frequency Computer Analysis Program (RAFCAP) for calculating the EM noise generated by valve ignition of a converter station has been developed as part of a larger project. The program calculates RF voltages, currents, complex power, ground level electric field strength and magnetic flux density in and around an HVDC converter station. The program requires the converter station network to be represented by frequency dependent impedance functions. Comparisons of calculated and measured values are given for an actual HVDC station to illustrate the validity of the program. RAFCAP is designed to be used by engineers for the purpose of calculating the RF noise produced by the igniting of HVDC converter valves.

Kasten, D.G.; Caldecott, R.; Sebo, S.A. (Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering); Liu, Y. (Virginia Polytechnic Inst. State Univ., Blacksburg, VA (United States). Bradley Dept. of Electrical Engineering)

1994-04-01T23:59:59.000Z

398

The MuCool Test Area and RF Program  

SciTech Connect (OSTI)

The MuCool RF Program focuses on the study of normal conducting RF structures operating in high magnetic field for applications in muon ionization cooling for Neutrino Factories and Muon Colliders. This paper will give an overview of the program, which will include a description of the test facility and its capabilities, the current test program, and the status of a cavity that can be rotated in the magnetic field which allows for a more detailed study of the maximum stable operating gradient vs. magnetic field strength and angle.

Bross, A D; Jansson, A; Moretti, A; Yonehara, K; Huang, D; Torun, Y; Li, D; Norem, J; Palmer, R B; Stratakis, D

2010-05-01T23:59:59.000Z

399

The Los Alamos VXI-based modular RF control system  

SciTech Connect (OSTI)

This paper describes the design and implementation of the Los Alamos modular RF control system, which provides high-performance feedback and/or feedforward control of RF accelerator cavities. This is a flexible, modular control system which has been realized in the industry-standard VXI cardmodular format. A wide spectrum of system functionality can be accommodated simply by incorporating only those modules and features required for a particular application. The fundamental principles of the design approach are discussed. Details of the VXI implementation are given, including the system architecture and interfaces, performance capabilities, and available features.

Jachim, S.P.; Ziomek, C.; Natter, E.F.; Regan, A.H.; Hill, J.; Eaton, L.; Gutscher, W.D.; Curtin, M.; Denney, P.; Hansberry, E.; Brooks, T.

1993-06-01T23:59:59.000Z

400

The Los Alamos VXI-based modular RF control system  

SciTech Connect (OSTI)

This paper describes the design and implementation of the Los Alamos modular RF control system, which provides high-performance feedback and/or feedforward control of RF accelerator cavities. This is a flexible, modular control system which has been realized in the industry-standard VXI cardmodular format. A wide spectrum of system functionality can be accommodated simply by incorporating only those modules and features required for a particular application. The fundamental principles of the design approach are discussed. Details of the VXI implementation are given, including the system architecture and interfaces, performance capabilities, and available features.

Jachim, S.P.; Ziomek, C.; Natter, E.F.; Regan, A.H.; Hill, J.; Eaton, L.; Gutscher, W.D.; Curtin, M.; Denney, P.; Hansberry, E.; Brooks, T.

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Plasma Acceleration from RF Discharge in Dielectric Capillary  

SciTech Connect (OSTI)

Plasma acceleration from rf discharge in dielectric capillary was demonstrated. Observed plasma flow had ion energies of approximately 100 eV and electron energies of approximately 20 eV. The discharge was powered by a MHz-range rf generator and fed by Ar. Experimental results indicate possible validity of assumptions about formation of a potential difference at the open end of the capillary and presence of hot electron fraction in the capillary discharge. Simplicity and small dimensions of the source are attractive for micro-propulsion applications.

A. Dunaevsky; Y. Raitses; N. J. Fisch

2005-08-09T23:59:59.000Z

402

CONCEPTUAL DESIGN OF A BRIGHT ELECTRON INJECTOR BASED ON A LASER-DRIVEN PHOTOCATHODE RF ELECTRON GUN  

E-Print Network [OSTI]

Photocathode RF Electron Gun S. Chattopadhyay, Y.J. Chen, D.PHOTOCATHODE RF ELECTRON GUN' S. Chnttopndhyny. Y.J. Chen (Photocathode RF Electron Gun S. Chattopadhyay, Y.I. Chen, D.

Chattopadhyay, S.

2010-01-01T23:59:59.000Z

403

Spontaneous Emission Near Superconducting Bodies  

E-Print Network [OSTI]

In the present paper we study the spontaneous photon emission due to a magnetic spin-flip transition of a two-level atom in the vicinity of a dielectric body like a normal conducting metal or a superconductor. For temperatures below the transition temperature T_c of a superconductor, the corresponding spin-flip lifetime is boosted by several orders of magnitude as compared to the case of a normal conducting body. Numerical results of an exact formulation are also compared to a previously derived approximative analytical expression for the spin-flip lifetime and we find an excellent agreement. We present results on how the spin-flip lifetime depends on the temperature T of a superconducting body as well as its thickness H. Finally, we study how non-magnetic impurities as well as possible Eliashberg strong-coupling effects influence the spin-flip rate. It is found that non-magnetic impurities as well as strong-coupling effects have no dramatic impact on the spin-flip lifetime.

Bo-Sture K. Skagerstam; Per Kristian Rekdal

2007-06-07T23:59:59.000Z

404

E-Print Network 3.0 - angle rf pulses Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

pulse operating on M: RFx pulse operating on FZ: RF pulses K-Space Scheffler 1999: PDF... " cos() 2 sin2 ( 2) 1st 1st RF pulse 12;E. Wong, BE278, UCSD Winter 2011...

405

Advances in Filter Miniaturization and Design/Analysis of RF MEMS Tunable Filters  

E-Print Network [OSTI]

The main purpose of this dissertation was to address key issues in the design and analysis of RF/microwave filters for wireless applications. Since RF/microwave filters are one of the bulkiest parts of communication systems, their miniaturization...

Sekar, Vikram

2012-10-19T23:59:59.000Z

406

Advances in Broadband RF Sensing for Real-time Control of Plasma-Based Semiconductor Processing  

E-Print Network [OSTI]

to standard RF metrology. The system uses an antenna in the glow discharge to excite the bulk plasma identification of process conditions for standard RF sensing, and 99:5 correct identification of process

Grizzle, Jessy W.

407

E-Print Network 3.0 - accelerating rf station Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

by a 1.25-T -decay channel with phase-rotation via rf (to compress... to beam tests; Test 70-MHz rf cavity (+ 1.25-T magnet) 3 m from target; Characterize ... Source:...

408

Anisotropic transport properties of ferromagnetic-superconducting bilayers  

E-Print Network [OSTI]

We study the transport properties of vortex matter in a superconducting thin film separated by a thin insulator layer from a ferromagnetic layer. We assume an alternating stripe structure for both FM and superconducting (SC) layers as found in S...

Kayali, MA; Pokrovsky, Valery L.

2004-01-01T23:59:59.000Z

409

Superconducting magnets for muon capture and phase rotation  

E-Print Network [OSTI]

of Various Cases for Superconducti ng Magnets Inside andTransactions on Applied Superconductivity 7, No 2. P 642 (LBNL-43998 SC-MAG-683 SUPERCONDUCTING MAGNETS FOR MUON

Green, M.A.

2011-01-01T23:59:59.000Z

410

MATHEMATICAL ANALYSIS OF CONDUCTING AND SUPERCONDUCTING TRANSMISSION LINES  

E-Print Network [OSTI]

MATHEMATICAL ANALYSIS OF CONDUCTING AND SUPERCONDUCTING TRANSMISSION LINES ANNE-SOPHIE BONNET propagation in the microstrip transmission lines used in microelectronics. In the first part, the case of the perfectly conducting strip. Key words. superconducting transmission lines, waveguides, spectral analysis

Ramdani, Karim - Institut de Mathématiques �lie Cartan, Université Henri Poincaré

411

High Temperature Superconductivity in Cuprates: a model  

E-Print Network [OSTI]

A model is proposed such that quasi-particles (electrons or holes) residing in the CuO2 planes of cuprates may interact leading to metallic or superconducting behaviors. The metallic phase is obtained when the quasi-particles are treated as having classical kinetic energies and the superconducting phase occurs when the quasi-particles are taken as extremely relativistic objects. The interaction between both kinds of particles is provided by a force dependent-on-velocity. In the case of the superconducting behavior, the motion of apical oxygen ions provides the glue to establish the Cooper pair. The model furnishes explicit relations for the Fermi velocity, the perpendicular and the in-plane coherence lengths, the zero-temperature energy gap, the critical current density, the critical parallel and perpendicular magnetic fields. All these mentioned quantities are expressed in terms of fundamental physical constants as: charge and mass of the electron, light velocity in vacuum, Planck constant, electric permittivity of the vacuum. Numerical evaluation of these quantities show that their values are close those found for the superconducting YBaCuO, leading to think the model as being a possible scenario to explain superconductivity in cuprates.

P. R. Silva

2010-07-16T23:59:59.000Z

412

Color superconductivity and dense quark matter  

E-Print Network [OSTI]

The properties of cold and dense quark matter have been the subject of extensive investigation, especially in the last decade. Unfortunately, we still lack of a complete understanding of the properties of matter in these conditions. One possibility is that quark matter is in a color superconducting phase which is characterized by the formation of a diquark condensate. We review some of the basic concepts of color superconductivity and some of the aspects of this phase of matter which are relevant for compact stars. Since quarks have color, flavor as well as spin degrees of freedom many different color superconducting phases can be realized. At asymptotic densities QCD predicts that the color flavor locked phase is favored. At lower densities where the QCD coupling constant is large, perturbative methods cannot be applied and one has to rely on some effective model, eventually trying to constrain such a model with experimental observations. The picture is complicated by the requirement that matter in the interior of compact stars is in weak equilibrium and neutral. These conditions and the (possible) large value of the strange quark mass conspire to separate the Fermi momenta of quarks with different flavors, rendering homogenous superconducting phases unstable. One of the aims of this presentation is to introduce non-experts in the field to some of the basic ideas of color superconductivity and to some of its open problems.

Massimo Mannarelli

2008-12-26T23:59:59.000Z

413

MEDIUM POWER 352 MHZ SOLID STATE PULSED RF AMPLIFIERS FOR THE CERN LINAC4 PROJECT  

E-Print Network [OSTI]

MEDIUM POWER 352 MHZ SOLID STATE PULSED RF AMPLIFIERS FOR THE CERN LINAC4 PROJECT J. Broere, J in the CERN Linac4. The amplifiers are water-cooled and can provide up to 33 kW pulsed RF Power, 1.5 ms pulse RF Power for the debuncher cavity. The concept is based on 1.2 kW RF power modules using the latest 6

Paris-Sud XI, Université de

414

Towards Computing Ratcheting and Training in Superconducting Magnets  

E-Print Network [OSTI]

Towards Computing Ratcheting and Training in Superconductingcomputational results of the ratcheting process, the impactright). Index Terms—Ratcheting, superconducting magnet,

Ferracin, Paolo

2009-01-01T23:59:59.000Z

415

Development of RF CMOS receiver front-ends for ultrawideband  

E-Print Network [OSTI]

demonstrates two different solutions for the RF front-end designs in the UWB receivers, one is distributed topology, and the other is based on traditional lumped element topology. The distributed amplifier is one of the attractive candidates for UWB Low Noise...

Guan, Xin

2009-05-15T23:59:59.000Z

416

COLLISIONLESS ELECTRON HEATING IN RF GAS DISCHARGES: I. QUASILINEAR THEORY  

E-Print Network [OSTI]

COLLISIONLESS ELECTRON HEATING IN RF GAS DISCHARGES: I. QUASILINEAR THEORY Yu.M. Aliev1 , I an interest in mechanisms of electron heating and power deposition in the plasma main- tained by radio parameters. Due to the large value of the mean free path (MFP) the main mechanism of electron heating turns

Kaganovich, Igor

417

RF power potential of 45 nm CMOS technology  

E-Print Network [OSTI]

This paper presents the first measurements of the RF power performance of 45 nm CMOS devices with varying device widths and layouts. We find that 45 nm CMOS can deliver a peak output power density of around 140 mW/mm with ...

Putnam, Christopher

418

Novel Reactor Relevant RF Actuator Schemes for the Lower  

E-Print Network [OSTI]

location for RF launchers · Transport in tokamak sends heat and particles to low field side SOL: ­ Forces reactor is challenging: ­ Survivability is a major issue because of the harsh environment high heat solution that both mitigates PMI / coupling problems and improves core wave physics issues. #12;Reactor

419

Beyond ITER: RF Heating and Current Drive Issues for DEMO  

E-Print Network [OSTI]

control Need to operate reliably in a high power flux, high radiation, and "steady state" nuclear lose 10% or more power to edge / vessel ­ Minimal diagnostic support for RF edge interactions systems do not yet run for extended time periods #12;Facilities that provide a DEMO-relevant testing

Princeton Plasma Physics Laboratory

420

Multiband Antenna-Receiver Integration using an RF Multiplexer with Sensitivity-Constrained Design  

E-Print Network [OSTI]

S.M. Shajedul Hasan (hasan@vt.edu) Steven Ellingson (ellingson@vt.edu) RF Multiplexer Hasan be largely mitigated by: · Implementing design to be robust to variations RF Multiplexer Hasan / Ellingson #12;Motivation (2/2) Focus of this paper System Diagram of the prototype MMR RF Multiplexer Hasan

Ellingson, Steven W.

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Multiband Antenna-Receiver Integration using an RF Multiplexer with Sensitivity-Constrained Design  

E-Print Network [OSTI]

S.M. Hasan and S. W. Ellingson Wireless at Virginia Tech RF Multiplexer Hasan / Ellingson ­ July 10 be largely mitigated by: 2/14 RF Multiplexer Hasan / Ellingson ­ July 10, 2008 RFIC from Motorola Research (2/2) Focus of this paper System Diagram of the prototype MMR 3/14 RF Multiplexer Hasan / Ellingson

Ellingson, Steven W.

422

Identification of Residual Stress State in an RF-MEMS Device  

E-Print Network [OSTI]

of wafer level tests. The membrane is part of an RF MEMS Switch man- ufactured by Raytheon Systems Co) and 3D numerical simulations. THE RAYTHEON'S RF MEMS SWITCH The RF MEMS switch technology developed by Raytheon Systems Co. provides advantageous characteristics for communication circuits by virtue of its

Espinosa, Horacio D.

423

PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*)  

E-Print Network [OSTI]

L-435 PERCOLATION AND SUPERCONDUCTIVITY IN ION-IMPLANTED ALUMINIUM FILMS (*) F. MEUNIER and P of Si and Ge in Al thin films at 8 K produces alloys exhibiting enhanced superconducting transition in the superconducting transition temperature Tc of several such alloys [2], [5], [6] : Josephson tunnelling

Boyer, Edmond

424

The millimeter-wave properties of superconducting microstrip lines  

E-Print Network [OSTI]

The millimeter-wave properties of superconducting microstrip lines A. Vayonakis£, C. Luo , H of the millimeter-wave properties of superconducting thin-film microstrip transmission lines. Our exper- imental, with a temperature-independent loss tangent of 5 3 ¦0 5 ¢10 3 for our samples. INTRODUCTION Superconducting

425

Study on the energy criterion of cuprate superconductivity  

E-Print Network [OSTI]

In this paper, we use the variation of spontaneous magnetization to describe the influence of electron holes in cuprate superconductors, and use competitive energy relations to explore the superconductivity rule and energy criterion, on this basis, we can deduce a clear physical image of superconducting phase diagram and superconducting mechanism.

Gu Jiapu

2010-02-09T23:59:59.000Z

426

Superconducting Wires Enabled by Nanodots wins Nano50TM Award  

E-Print Network [OSTI]

includes nanoscale columns of non-superconducting material embedded within the superconductorSuperconducting Wires Enabled by Nanodots wins Nano50TM Award HTS Wires Enabled via 3D Self-Assembly of Insulating Nanodots Background · For most large-scale applications of high-temperature superconducting (HTS

427

Singlet oxygen luminescence detection with a fibre-coupled superconducting  

E-Print Network [OSTI]

Singlet oxygen luminescence detection with a fibre-coupled superconducting nanowire single luminescence detection Fibre-based singlet oxygen luminescence detection References Superconducting Detector, is an intermediate in many biological processes. We employ a superconducting nanowire single-photon detector (SNSPD

Greenaway, Alan

428

Design of a Superconducting Quantum Computer Prof. John Martinis  

E-Print Network [OSTI]

Design of a Superconducting Quantum Computer Prof. John Martinis University of California Date building (Faculty of Materials Science and Engineering) #12;Design of a Superconducting Quantum Computer Superconducting quantum computing is now at an important crossroad, where "proof of concept" experiments involving

Rimon, Elon

429

A model for variable thickness superconducting thin lms  

E-Print Network [OSTI]

A model for variable thickness superconducting thin #12;lms S. J. Chapman #3; Mathematical for Applied Mathematics Virginia Tech Blacksburg VA 24061-0531, USA Abstract A model for superconductivity. When the #12;lm is of uniform thickness the model is identical to a model for superconducting cylinders

Chapman, Jon

430

Superconducting Properties MgB 2 from First Principles  

E-Print Network [OSTI]

Superconducting Properties MgB 2 from First Principles Floris, Profeta, Lathiotakis, 1 LuË?ders, 4 M, such very high superconducting transition temperature. Focusing on compound, report first nontrivial.25.Jb, 71.15.Mb, -- 74.70.Ad Understanding and predicting superconducting proper­ ties real materials

Gross, E.K.U.

431

Entanglement and Quantum Error Correction with Superconducting Qubits  

E-Print Network [OSTI]

Entanglement and Quantum Error Correction with Superconducting Qubits A Dissertation Presented David Reed All rights reserved. #12;Entanglement and Quantum Error Correction with Superconducting is to use superconducting quantum bits in the circuit quantum electro- dynamics (cQED) architecture. There

432

Superconducting Magnets Research for a Viable US Fusion Program  

E-Print Network [OSTI]

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini, Leslie Superconductivity Center, Florida State University 2014 FESAC Strategic Planning (SP) Panel June 5, 2014 program now has the opportunity to take a world- leading role in making high field superconducting magnets

433

Superconducting technology program: Sandia 1995 annual report  

SciTech Connect (OSTI)

Sandia`s STP program is a thallium-based high-temperature superconductor (HTS) research and development program consisting of efforts in powder synthesis and process development, open-system thick film conductor development, wire and tape fabrication, and HTS motor design. The objective of this work is to develop high-temperature superconducting conductors (wire and tape) capable of meeting requirements for high-power electrical devices of interest to industry. The research efforts currently underway are: (1) process development and characterization of thallium-based high-temperature superconducting closed system wire and tape; (2) investigation of the synthesis and processing of thallium-based thick films using two-zone processing; and (3) cryogenic design of a 30K superconducting motor. This report outlines the research that has been performed during FY95 in each of these areas.

Roth, E.P. [Sandia National Labs., Albuquerque, NM (United States). Superconductivity Materials and Technology Dept.

1996-03-01T23:59:59.000Z

434

Comparative Analysis of Carbon Plasma in Arc and RF Reactors  

SciTech Connect (OSTI)

Results on studies of molecular spectra emitted in the initial stages of fullerene formation during the processing of graphite powder in induction RF reactor and evaporation of graphite electrodes in arc reactor are presented in this paper. It was found that C2 radicals were dominant molecular species in both plasmas. C2 radicals have an important role in the process of fullerene synthesis. The rotational-vibrational temperatures of C2 and CN species were calculated by fitting the experimental spectra to the simulated ones. The results of optical emission study of C2 radicals generated in carbon arc plasma have shown that rotational temperature of C2 species depends on carbon concentration and current intensity significantly. The optical emission study of induction RF plasma and SEM analysis of graphite powder before and after plasma treatment have shown that evaporation of the processed graphite powder depends on feed rate and composition of gas phase significantly. Based on the obtained results, it was concluded that in the plasma region CN radicals could be formed by the reaction of C2 species with atomic nitrogen at smaller loads. At larger feed rate of graphite powder, CN species were produced by surface reaction of the hot carbon particles with nitrogen atoms. The presence of nitrogen in induction RF plasma reduces the fullerene yield significantly. The fullerene yield obtained in two different reactors was: 13% in arc reactor and 4.1% in induction RF reactor. However, the fullerene production rate was higher in induction RF reactor-6.4 g/h versus 1.7 g/h in arc reactor.

Todorovic-Markovic, B.; Markovic, Z. ['Vinca' Institute of Nuclear Sciences, P.O.B. 522, 11001 Belgrade (Serbia and Montenegro); Mohai, I.; Szepvolgyi, J. [Research Laboratory of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences H-1525 Budapest, POB 17 (Hungary)

2004-12-01T23:59:59.000Z

435

Direct observation of superconducting vortex clusters pinned by a periodic array of magnetic dots in ferromagnetic/superconducting hybrid structures  

E-Print Network [OSTI]

Direct observation of superconducting vortex clusters pinned by a periodic array of magnetic dots in ferromagnetic/superconducting hybrid structures T. Shapoval,1,* V. Metlushko,2 M. Wolf,1 B. Holzapfel,1 V. Neu,1, Illinois 60612, USA Received 13 November 2009; published 11 March 2010 Strong pinning of superconducting

Metlushko, Vitali

436

Recent Developments in High Temperature Superconductivity  

E-Print Network [OSTI]

three-dimensional superconductor which can be teclmologically important if its superconducting transition Tc can be enhanced to be above the temperature liquid nitrogen. Possible superconductivity above room temperature has been reported in a... mixture of CuBr and CuBr2 system [8]. A mid-point resistive transition of 346K (73C) is observed but it is not confirmed by magnetic measurements. BCSCO and TCBCO The new series of high Tc superconductors is characterized by the chemical formula A2B2...

Hor, P. H.

437

Apparatus for characterizing conductivity of superconducting materials  

DOE Patents [OSTI]

Apparatus and method for noncontact, radio-frequency shielding current characterization of materials. Self- or mutual inductance changes in one or more inductive elements, respectively, occur when materials capable of supporting shielding currents are placed in proximity thereto, or undergo change in resistivity while in place. Such changes can be observed by incorporating the inductor(s) in a resonant circuit and determining the frequency of oscillation or by measuring the voltage induced on a coupled inductive element. The present invention is useful for determining the critical temperature and superconducting transition width for superconducting samples. 10 figures.

Doss, J.D.

1993-12-07T23:59:59.000Z

438

Realization of a superconducting atom chip  

E-Print Network [OSTI]

We have trapped rubidium atoms in the magnetic field produced by a superconducting atom chip operated at liquid Helium temperatures. Up to $8.2\\cdot 10^5$ atoms are held in a Ioffe-Pritchard trap at a distance of 440 $\\mu$m from the chip surface, with a temperature of 40 $\\mu$K. The trap lifetime reaches 115 s at low atomic densities. These results open the way to the exploration of atom--surface interactions and coherent atomic transport in a superconducting environment, whose properties are radically different from normal metals at room temperature.

Thomas Nirrengarten; Angie Qarry; Cédric Roux; Andreas Emmert; Gilles Nogues; Michel Brune; Jean-Michel Raimond; Serge Haroche

2006-10-09T23:59:59.000Z

439

Criterion of stability of the superconducting state  

E-Print Network [OSTI]

In this paper, we propose to draw attention to the stability criterion of the superconductor current state. We use for this purpose the rough systems mathematical apparatus allowing us to relate the desired criterion with the dielectric permittivity of the matter and to identify the type of all possible phonons trajectories in its superconducting state. The state of superconductivity in the matter can be explained only by the phonons behavior peculiarity. And on the basis of the above-mentioned assumption, the corresponding mathematical model is constructed.

Iogann Tolbatov

2009-10-23T23:59:59.000Z

440

Induced Magnetism in Color-Superconducting Media  

E-Print Network [OSTI]

The dense core of compact stars is the natural medium for the realization of color superconductivity. A common characteristic of such astrophysical objects is their strong magnetic fields, especially those of the so called magnetars. In this talk, I discuss how a color superconducting core can generate or/and enhance the stellar magnetic field independently of a magnetohydrodynamic dynamo mechanism. The magnetic field generator is in this case a gluonic current which circulates to stabilize the color superconductor in the presence of a strong magnetic field or under the pairing stress produced in the medium by the neutrality and $\\beta$-equilibrium constraints.

Efrain J. Ferrer

2010-01-22T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

SQCD, Superconducting Gaps and Cyclic RG Flows  

E-Print Network [OSTI]

We consider the relation between the \\Omega -deformed N=2 SQCD with the single deformation parameter and integrable models of the BCS-like superconductivity. It is argued that the vortex string worldsheet theory is related to the Russian Doll(RD) model of the truncated BCS superconductivity. We argue that the \\Omega -deformed gauge theory manifests the interesting cyclic RG behavior with the period of the RG cycle proportional to \\epsilon^{-1}. The deformed gauge theory can develop several non-perturbative scales. We conjecture on the monopole bound state interpretation of the Efimov tower.

Alexander Gorsky

2012-02-20T23:59:59.000Z

442

Superconductivity with Stripes | Advanced Photon Source  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystalline Gallium OxideSumin KimSuperconductingSuperconductivityHow HIV

443

A prototype high-temperature superconducting coil for the 32 T all-superconducting magnet was constructed with YBCO tape and  

E-Print Network [OSTI]

A prototype high-temperature superconducting coil for the 32 T all- superconducting magnet T All-Superconducting Magnet Hubertus W. Weijers, W.D. Markiewicz, H. Bai, S.T. Hannahs National High

Weston, Ken

444

Quantum network of superconducting qubits through opto-mechanical interface  

E-Print Network [OSTI]

We propose a scheme to realize quantum networking of superconducting qubits based on the opto-mechanical interface. The superconducting qubits interact with the microwave photons, which then couple to the optical photons through the opto-mechanical interface. The interface generates a quantum link between superconducting qubits and optical flying qubits with tunable pulse shapes and carrier frequencies, enabling transmission of quantum information to other superconducting or atomic qubits. We show that the scheme works under realistic experimental conditions and it also provides a way for fast initialization of the superconducting qubits under 1 K instead of 20 mK operation temperature.

Zhang-qi Yin; W. L. Yang; L. Sun; L. M. Duan

2015-01-08T23:59:59.000Z

445

Superconducting fault current-limiter with variable shunt impedance  

DOE Patents [OSTI]

A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

Llambes, Juan Carlos H; Xiong, Xuming

2013-11-19T23:59:59.000Z

446

The Cost of Superconducting Magnets as a Function of Stored Energy and Design Magnetic Induction Times the Field Volume  

E-Print Network [OSTI]

the Cost of Large Superconducting Thin Solenoid Magnets,"The Economics of Large Superconducting Toroidal Magnets forEnergy (MJ) Fig. 2. Superconducting magnet costs (M$) versus

Green, M.A.

2008-01-01T23:59:59.000Z

447

Superconducting Technology Program Sandia 1994 Annual Report  

SciTech Connect (OSTI)

Sandia`s STP program is a four-part high-temperature superconductor (HTS) research and development program consisting of efforts in powder synthesis and process development, thallium-based HTS film development, wire and tape fabrication, and HTS motor design. The objective of this work is to develop high-temperature superconducting conductors (wire and tape) capable of meeting requirements for high-power electrical devices of interest to industry. The four research efforts currently underway are: (1) Process research on the material synthesis of high-temperature superconductors, (2) Investigation of the synthesis and processing of thallium-based high-temperature superconducting thick films, (3) Process development and characterization of high-temperature superconducting wire and tape, and (4) Cryogenic design of a high-temperature superconducting motor. This report outlines the research that has been performed during FY94 in each of these four areas. Major areas of research are described, although no attempt has been made to exhaustively include all work performed in each of these areas.

Roth, E.P.

1995-10-01T23:59:59.000Z

448

High temperature superconducting fault current limiter  

DOE Patents [OSTI]

A fault current limiter for an electrical circuit is disclosed. The fault current limiter includes a high temperature superconductor in the electrical circuit. The high temperature superconductor is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter. 15 figs.

Hull, J.R.

1997-02-04T23:59:59.000Z

449

Positive and inverse isotope effect on superconductivity  

E-Print Network [OSTI]

This article improves the BCS theory to include the inverse isotope effect on superconductivity. An affective model can be deduced from the model including electron-phonon interactions, and the phonon-induced attraction is simply and clearly explained on the electron Green function. The focus of this work is on how the positive or inverse isotope effect occurs in superconductors.

Tian De Cao

2009-09-04T23:59:59.000Z

450

Geometrical Dynamics in a Transitioning Superconducting Sphere  

E-Print Network [OSTI]

Recent theoretical work has concentrated on calculating the Casimir effect in curved spacetime. In this paper we outline the forward problem of metrical variation due to the Casimir effect for spherical geometries. We consider a scalar quantum field inside a hollow superconducting sphere. Metric equations are developed describing the evolution of the scalar curvature after the sphere transitions to the normal state.

James R. Claycomb; Rambis K. Chu

2006-02-22T23:59:59.000Z

451

Flux Exclusion Superconducting Quantum Metamaterial: Towards  

E-Print Network [OSTI]

. Recently, arrays of Josephson junction devices have been proposed as a possible solution. However-atoms containing Josephson junctions15­19 , experiments have been conducted on single superconducting qubit meta-atoms20,21 and one- dimensional Josephson junction metamaterials22 . The recently discovered class of iron

Zheludev, Nikolay

452

Aluminum in Superconducting Magnets Robert J. Weggel  

E-Print Network [OSTI]

Aluminum in Superconducting Magnets Robert J. Weggel Magnet Optimization Research Engineering is aluminum, either ultrapure, as quenchstabilization matrix metal, and/or alloyed and coldworked and heat for magnets in which the stresses and strains are modest. The strongest aluminum alloy commercially available

McDonald, Kirk

453

RIA Superconducting Drift Tube Linac R & D  

SciTech Connect (OSTI)

Cavity and cryomodule development work for a superconducting ion linac has been underway for several years at the National Superconducting Cyclotron Laboratory. The original application of the work was the proposed Rare Isotope Accelerator. At present, the work is being continued for use with the Facility for Rare Isotope Beams (FRIB). The baseline linac for FRIB requires 4 types of superconducting cavities to cover the velocity range needed to accelerate an ion beam to #21; 200 MeV/u: 2 types of quarter-wave resonator (QWR) and 2 types of half-wave resonator (HWR). Superconducting solenoids are used for focussing. Active and passive shielding is required to ensure that the solenoids’ field does not degrade the cavity performance. First prototypes of both QWR types and one HWR type have been fabricated and tested. A prototype solenoid has been procured and tested. A test cryomodule has been fabricated and tested. The test cryomodule contains one QWR, one HWR, one solenoid, and one super-ferric quadrupole. This report covers the design, fabrication, and testing of this cryomodule

J. Popielarski; J. Bierwagen; S. Bricker; C. Compton; J. DeLauter; P. Glennon; T. Grimm; W. Hartung; D. Harvell; M. Hodek; M. Johnson; F. Marti; P. Miller; A. Moblo; D. Norton; L. Popielarski; J. Wlodarczak; R. C. York; A. Zeller

2009-05-22T23:59:59.000Z

454

Kink in superconducting cosmic string: exact solution  

E-Print Network [OSTI]

We solve the equations of motion and find the Lorentz transformation associated with a kink in superconducting cosmic string. The kink velocity does not depend on its amplitude. The kink amplitude cannot be arbitrary but it varies within definite range and determines the explicit form of the relevant Lorentz transformation.

Ernst Trojan

2014-12-24T23:59:59.000Z

455

Induction heating of FeCo nanoparticles for rapid rf curing of epoxy K. J. Miller,1,a  

E-Print Network [OSTI]

, and cracking of the polymer. An alternative curing process involves remote, noncontact rf heating of MNP loadedInduction heating of FeCo nanoparticles for rapid rf curing of epoxy composites K. J. Miller,1,a K epoxy composites through radio-frequency rf heating. The rf response of functionalized FeCo MNPs

McHenry, Michael E.

456

Free electron laser using Rf coupled accelerating and decelerating structures  

DOE Patents [OSTI]

A free electron laser and free electron laser amplifier using beam transport devices for guiding an electron beam to a wiggler of a free electron laser and returning the electron beam to decelerating cavities disposed adjacent to the accelerating cavities of the free electron laser. Rf energy is generated from the energy depleted electron beam after it emerges from the wiggler by means of the decelerating cavities which are closely coupled to the accelerating cavities, or by means of a second bore within a single set of cavities. Rf energy generated from the decelerated electron beam is used to supplement energy provided by an external source, such as a klystron, to thereby enhance overall efficiency of the system.

Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

457

Performance of Magnesium Cathode in the S Band RF Gun  

SciTech Connect (OSTI)

In this paper, we present the preliminary results of the performance of magnesium cathode in a high frequency RF gun. The quantum efficiency of magnesium showed a dramatic improvement upon laser cleaning, increasing from 10{sup -5} to 4x10{sup -4} after two hours of cleaning. The spatial uniformity of emission also improved from a spot to spot variation of 10 to a variation of 2. Measurements with charges >1 nC indicate that the transient variation of the field due to the shielding effect of the electron in the vicinity of the cathode may play a critical role in the efficient extraction of electrons. Comprehensive theory that includes the electron emission in the presence of a time dependent Schottky effect and RF effects will be discussed.

Srinivasan-Rao, T.; /Brookhaven; Palmer, D.T.; /SLAC; Ben-Zvi, I.; /Brookhaven; Miller, R.H.; /SLAC; Wang, X.J.; Woodle, M.; /Brookhaven

2011-09-01T23:59:59.000Z

458

DEPOSITION OF NIOBIUM AND OTHER SUPERCONDUCTING MATERIALS WITH HIGH POWER IMPULSE MAGNETRON SPUTTERING: CONCEPT AND FIRST RESULTS  

SciTech Connect (OSTI)

Niobium coatings on copper cavities have been considered as a cost-efficient replacement of bulk niobium RF cavities, however, coatings made by magnetron sputtering have not quite lived up to high expectations due to Q-slope and other issues. High power impulse magnetron sputtering (HIPIMS) is a promising emerging coatings technology which combines magnetron sputtering with a pulsed power approach. The magnetron is turned into a metal plasma source by using very high peak power density of ~ 1 kW/cm{sup 2}. In this contribution, the cavity coatings concept with HIPIMS is explained. A system with two cylindrical, movable magnetrons was set up with custom magnetrons small enough to be inserted into 1.3 GHz cavities. Preliminary data on niobium HIPIMS plasma and the resulting coatings are presented. The HIPIMS approach has the potential to be extended to film systems beyond niobium, including other superconducting materials and/or multilayer systems.

High Current Electronics Institute, Tomsk, Russia; Anders, Andre; Mendelsberg, Rueben J.; Lim, Sunnie; Mentink, Matthijs; Slack, Jonathan L.; Wallig, Joseph G.; Nollau, Alexander V.; Yushkov, Georgy Yu.

2011-07-24T23:59:59.000Z

459

Observation of pedestal turbulence in edge localized mode-free H-mode on experimental advanced superconducting tokamak  

SciTech Connect (OSTI)

Two different pedestal turbulence structures have been observed in edge localized mode-free phase of H-mode heated by lower hybrid wave and RF wave in ion cyclotron range of frequencies (ICRF) on experimental advanced superconducting tokamak. When the fraction of ICRF power P{sub ICRF}/P{sub total} exceeds 0.7, coherent mode is observed. The mode is identified as an electromagnetic mode, rotating in electron diamagnetic direction with a frequency around 50 kHz and toroidal mode number n?=??3. Whereas when P{sub ICRF}/P{sub total} is less than 0.7, harmonic mode with frequency f?=?40–300 kHz appears instead. The characteristics of these two modes are demonstrated preliminarily. The threshold value of heating power and also the plasma parameters are distinct.

Han, X., E-mail: hanx@ipp.ac.cn; Zhang, T.; Zhang, S. B.; Wang, Y. M.; Shi, T. H.; Liu, Z. X.; Kong, D. F.; Qu, H.; Gao, X. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China)

2014-10-15T23:59:59.000Z

460

RF generation in the DARHT Axis-II beam dump  

SciTech Connect (OSTI)

We have occasionally observed radio-frequency (RF) electromagnetic signals in the downstream transport (DST) of the second axis linear induction accelerator (LIA) at the dual-axis radiographic hydrodynamic testing (DARHT) facility. We have identified and eliminated some of the sources by eliminating the offending cavities. However, we still observe strong RF in the range 1 GHz t0 2 GHz occurring late in the {approx}2-{micro}s pulse that can be excited or prevented by varying the downstream tune. The narrow frequency width (<0.5%) and near exponential growth at the dominant frequency is indicative of a beam-cavity interaction, and electro-magnetic simulations of cavity structure show a spectrum rich in resonances in the observed frequency range. However, the source of beam produced RF in the cavity resonance frequency range has not been identified, and it has been the subject of much speculation, ranging from beam-plasma or beam-ion instabilities to unstable cavity coupling.

Ekdahl, Carl A. Jr. [Los Alamos National Laboratory

2012-05-03T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

1 -SUBTIDAL 2 -INTERTIDAL RB ROCK UB UNCONSOLIDATED AB AQUATIC BED RF -REEF OW -OPEN WATER/ AB AQUATIC BED RF REEF RS ROCKY SHORE US -UNCONSOLIDATED  

E-Print Network [OSTI]

M - MARINE 1 - SUBTIDAL 2 - INTERTIDAL RB ­ ROCK UB ­ UNCONSOLIDATED AB ­ AQUATIC BED RF - REEF OW - OPEN WATER/ AB ­ AQUATIC BED RF­ REEF RS ­ ROCKY SHORE US - UNCONSOLIDATED BOTTOM BOTTOM Unknown Bottom ­ UNCONSOLIDATED AB ­ AQUATIC RF ­ REEF OW - OPEN WATER/ AB ­ AQUATIC RF­ REEF SB ­ STREAMBED RS - ROCKY US

Gray, Matthew

462

Design, construction, system integration, and test results of the 1 MW CW RF system for the e-gun cavity in the energy recovery LINAC at Brookhaven National Laboratory  

SciTech Connect (OSTI)

Brookhaven's ERL (Energy Recovery LINAC) requires a 1 MW CW RF system for the superconducting electron gun cavity. The system consists primarily of a klystron tube, transmitter, and High-Voltage Power Supply (HVPS). The 703.75 MHz klystron made by CPl, Inc. provides RF power of 1MW CW with efficiency of 65%. It has a single output window, diode-type electron gun, and collector capable of dissipating the entire beam power. It was fully factory tested including 24-hour heat run at 1.1 MW CWo The solid state HVPS designed by Continental Electronics provides up to 100 kV at low ripple and 2.1 MW CW with over 95% efficiency. With minimal stored energy and a fast shut-down mode no crowbar circuit is needed. Continental 's transmitter includes PLC based user interface and monitoring, RF pre-amplifier, magnet and Vac-Ion pump supplies, cooling water instrumentation, and integral safety interlock system. BNL installed the klystron, HVPS, and transmitter along with other items, such as circulator, water load, and waveguide components. The collaboration of BNL, CPI, and Continental in the design, installation, and testing was essential to the successful operation of the 1MW system.

Lenci,S.J.; Eisen, E. L.; Dickey, D. L.; Sainz, J. E.; Utay, P. F.; Zaltsman, A.; Lambiase, R.

2009-05-04T23:59:59.000Z

463

10^{-7} contrast ratio at 4.5Lambda/D: New results obtained in laboratory experiments using nano-fabricated coronagraph and multi-Gaussian shaped pupil masks  

E-Print Network [OSTI]

We present here new experimental results on high contrast imaging of 10^{-7} at 4.5Lambda/D (Lambda = 0.820 microns) by combining a circular focal plane mask (coronagraph) of 2.5Lambda/D diameter and a multi-Gaussian pupil plane mask. Both the masks were fabricated on very high surface quality (Lambda/30) BK7 optical substrates using nano-fabrication techniques of photolithography and metal lift-off. This process ensured that the shaped masks have a useable edge roughness better than Lambda/4 (rms error better than 0.2 microns), a specification that is necessary to realize the predicted theoretical limits of any mask design. Though a theoretical model predicts a contrast level of 10^{-12}, the background noise of the observed images was speckle dominated which reduced the contrast level to 4x10^{-7} at 4.5Lambda/D. The optical setup was built on the University of Illinois Seeing Improvement System (UnISIS) optics table which is at the Coude focus of the 2.5-m telescope of the Mt. Wilson Observatory. We used a 0.820 micron laser source coupled with a 5 micron single-mode fiber to simulate an artificial star on the optical test bench of UnISIS.

Abhijit Chakraborty; Laird A. Thompson; Mike Rogosky

2005-04-05T23:59:59.000Z

464

Torsional texturing of superconducting oxide composite articles  

DOE Patents [OSTI]

A method of texturing a multifilamentary article having filaments comprising a desired oxide superconductor or its precursors by torsionally deforming the article is provided. The texturing is induced by applying a torsional strain which is at least about 0.3 and preferably at least about 0.6 at the surface of the article, but less than the strain which would cause failure of the composite. High performance multifilamentary superconducting composite articles having a plurality of low aspect ratio, twisted filaments with substantially uniform twist pitches in the range of about 1.00 inch to 0.01 inch (25 to 0.25 mm), each comprising a textured desired superconducting oxide material, may be obtained using this texturing method. If tighter twist pitches are desired, the article may be heat treated or annealed and the strain repeated as many times as necessary to obtain the desired twist pitch. It is preferred that the total strain applied per step should be sufficient to provide a twist pitch tighter than 5 times the diameter of the article, and twist pitches in the range of 1 to 5 times the diameter of the article are most preferred. The process may be used to make a high performance multifilamentary superconducting article, having a plurality of twisted filaments, wherein the degree of texturing varies substantially in proportion to the radial distance from the center of the article cross-section, and is substantially radially homogeneous at any given cross-section of the article. Round wires and other low aspect ratio multifilamentary articles are preferred forms. The invention is not dependent on the melting characteristics of the desired superconducting oxide. Desired oxide superconductors or precursors with micaceous or semi-micaceous structures are preferred. When used in connection with desired superconducting oxides which melt irreversibly, it provides multifilamentary articles that exhibit high DC performance characteristics and AC performance markedly superior to any currently available for these materials. In a preferred embodiment, the desired superconducting oxide material is BSCCO 2223.

Christopherson, Craig John (Grafton, MA); Riley, Jr., Gilbert N. (Marlborough, MA); Scudiere, John (Bolton, MA)

2002-01-01T23:59:59.000Z

465

Design of the fundamental power coupler and photocathode inserts for the 112MHz superconducting electron gun  

SciTech Connect (OSTI)

A 112 MHz superconducting quarter-wave resonator electron gun will be used as the injector of the Coherent Electron Cooling (CEC) proof-of-principle experiment at BNL. Furthermore, this electron gun can be the testing cavity for various photocathodes. In this paper, we present the design of the cathode stalks and a Fundamental Power Coupler (FPC) designated to the future experiments. Two types of cathode stalks are discussed. Special shape of the stalk is applied in order to minimize the RF power loss. The location of cathode plane is also optimized to enable the extraction of low emittance beam. The coaxial waveguide structure FPC has the properties of tunable coupling factor and small interference to the electron beam output. The optimization of the coupling factor and the location of the FPC are discussed in detail. Based on the transmission line theory, we designed a half wavelength cathode stalk which significantly brings down the voltage drop between the cavity and the stalk from more than 5.6 kV to 0.1 kV. The transverse field distribution on cathode has been optimized by carefully choosing the position of cathode stalk inside the cavity. Moreover, in order to decrease the RF power loss, a variable diameter design of cathode stalk has been applied. Compared to the uniform shape of stalk, this design gives us much smaller power losses in important locations. Besides that, we also proposed a fundamental power coupler based on the designed beam parameters for the future proof-of-principle CEC experiment. This FPC should give a strong enough coupling which has the Q external range from 1.5e7 to 2.6e8.

Xin, T.; Ben-Zvi, I.; Belomestnykh, S.; Chang, X.; Rao, T.; Skaritka, J.; Wu, Q.; Wang, E.; Liang, X.

2011-07-25T23:59:59.000Z

466

Color superconductivity with determinant interaction in strange quark matter  

E-Print Network [OSTI]

We investigate the effect of six fermion determinant interaction on color superconductivity as well as on chiral symmetry breaking. Coupled mass gap equations and the superconducting gap equation are derived through the minimisation of the thermodynamic potential. The effect of nonzero quark -- antiquark condensates on the superconducting gap is derived. This becomes particularly relevant for the case of 2-flavor superconducting matter with unpaired strange quarks in the diquark channel. While the effect of six fermion interaction leads to an enhancement of u-d superconductivity, due to nonvanishing strange quark--antiquark condensates, such an enhancement will be absent at higher densities for u-s or d-s superconductivity due to early (almost) vanishing of light quark-- antiquark condensates.

Amruta Mishra; Hiranmaya Mishra

2006-08-28T23:59:59.000Z

467

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini1  

E-Print Network [OSTI]

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini1 , Leslie fusion reactors rely on superconducting magnets for efficient and reliable production of these magnetic fields. Future superconducting magnets for fusion

468

Superconducting Magnets Research for a Viable US Fusion Program Joseph V. Minervini and Miklos Porkolab  

E-Print Network [OSTI]

Superconducting Magnets Research for a Viable US Fusion Program Joseph V rely on superconducting magnets for efficient and reliable production of these magnetic fields. Superconducting magnet technology is a powerful knob

469

Nb3Sn superconducting magnets for electron cyclotron resonance ion sources  

E-Print Network [OSTI]

the design of a N b S n superconducting magnet system for aNbjSn superconducting magnets for electron cyclotron5 C H 1 1 2 3 1 . Nb Sn superconducting magnets for electron

Ferracin, P.

2011-01-01T23:59:59.000Z

470

Excitation of Superconducting Qubits from Hot Nonequilibrium Quasiparticles J. Wenner,1  

E-Print Network [OSTI]

Excitation of Superconducting Qubits from Hot Nonequilibrium Quasiparticles J. Wenner,1 Yi Yin,1 manuscript received 4 March 2013; published 9 April 2013) Superconducting qubits probe environmental defects quasiparticles, with energies above the superconducting gap, affect qubits differently from quasiparticles

Martinis, John M.

471

Superconducting cuprate heterostructures for hot electron bolometers  

SciTech Connect (OSTI)

Transport properties of the resistive state of quasi-two dimensional superconducting heterostructures containing ultrathin La{sub 2?x}Sr{sub x}CuO{sub 4} layers synthesized using molecular beam epitaxy are studied. The electron transport exhibits strong deviation from Ohm's law, ?V??I{sup 3}, with a coefficient ?(T) that correlates with the temperature variation of the resistivity d?/dT. Close to the normal state, analysis of the nonlinear behavior in terms of electron heating yields an electron-phonon thermal conductance per unit area g{sub e?ph}?1 W/K cm{sup 2} at T = 20 K, one-two orders of magnitude smaller than in typical superconductors. This makes superconducting LaSrCuO heterostructures to be attractive candidate for the next generation of hot electron bolometers with greatly improved sensitivity.

Wen, B.; Yakobov, R.; Vitkalov, S. A. [Department of Physics, City College of New York, New York 10031 (United States)] [Department of Physics, City College of New York, New York 10031 (United States); Sergeev, A. [SUNY Research Foundation, SUNY at Buffalo, Buffalo, New York 14226 (United States)] [SUNY Research Foundation, SUNY at Buffalo, Buffalo, New York 14226 (United States)

2013-11-25T23:59:59.000Z

472

The ion pairs and superconducting bosons  

E-Print Network [OSTI]

First, it is shown that the creation of the spinless ion pairs in the lattice, which are hold by the binding with neighbor ion pairs together regarded as covalent. These ion pairs are created by the repulsive potential interaction of two ions which is bound as linear oscillator. The repulsive S-wave scattering between ion pairs and electrons is transformed to the attractive effective interaction between electrons which leads to a creation of electron pairs by a binding energy depending on the condensate fraction of ion pairs $\\frac{N_0}{N}$. In this respect, the absence of ion pairs in the condensate destroys a binding energy of electron pairs and in turn so-called superconductimg phase. As new result presented theory is that the number of the superconducting bosons is not changed in the superconducting phase.

V. N. Minasyan

2009-02-11T23:59:59.000Z

473

Superconductivity and the BCS-Bogoliubov Theory  

E-Print Network [OSTI]

First, we reformulate the BCS-Bogoliubov theory of superconductivity from the viewpoint of linear algebra. We define the BCS Hamiltonian on $\\mathbb{C}^{2^{2M}}$, where $M$ is a positive integer. We discuss selfadjointness and symmetry of the BCS Hamiltonian as well as spontaneous symmetry breaking. Beginning with the gap equation, we give the well-known expression for the BCS state and find the existence of an energy gap. We also show that the BCS state has a lower energy than the normal state. Second, we introduce a new superconducting state explicitly and show from the viewpoint of linear algebra that this new state has a lower energy than the BCS state. Third, beginning with our new gap equation, we show from the viewpoint of linear algebra that we arrive at the results similar to those in the BCS-Bogoliubov theory.

Shuji Watanabe

2010-06-07T23:59:59.000Z

474

Self-triggering superconducting fault current limiter  

DOE Patents [OSTI]

A modular and scaleable Matrix Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. The matrix fault current limiter comprises a fault current limiter module that includes a superconductor which is electrically coupled in parallel with a trigger coil, wherein the trigger coil is magnetically coupled to the superconductor. The current surge doing a fault within the electrical power network will cause the superconductor to transition to its resistive state and also generate a uniform magnetic field in the trigger coil and simultaneously limit the voltage developed across the superconductor. This results in fast and uniform quenching of the superconductors, significantly reduces the burnout risk associated with non-uniformity often existing within the volume of superconductor materials. The fault current limiter modules may be electrically coupled together to form various "n" (rows).times."m" (columns) matrix configurations.

Yuan, Xing (Albany, NY); Tekletsadik, Kasegn (Rexford, NY)

2008-10-21T23:59:59.000Z

475

Optomechanical-like coupling between superconducting resonators  

E-Print Network [OSTI]

We propose and analyze a circuit that implements a nonlinear coupling between two superconducting microwave resonators. The resonators are coupled through a superconducting quantum interference device (SQUID) that terminates one of the resonators. This produces a nonlinear interaction on the standard optomechanical form, where the quadrature of one resonator couples to the photon number of the other resonator. The circuit therefore allows for all-electrical realizations of analogs to optomechanical systems, with coupling that can be both strong and tunable. We estimate the coupling strengths that should be attainable with the proposed device, and we find that the device is a promising candidate for realizing the single-photon strong-coupling regime. As a potential application, we discuss implementations of networks of nonlinearly-coupled microwave resonators, which could be used in microwave-photon based quantum simulation.

J. R. Johansson; G. Johansson; Franco Nori

2014-03-18T23:59:59.000Z

476

Processing of superconductive materials and high frequency  

SciTech Connect (OSTI)

We do not know yet if superconductivity will become useful without refrigeration. Now, the superconductors are so different from copper that it is difficult to imagine replacing copper with such a brittle material. Superconductors conduct dc with no loss, ac with small losses, and microwaves in co-axial lines with almost no loss and with no dispersion from dc to the highest frequencies. They will probably allow us to close the gap between radio frequency and infrared optical transmission. Clearly your industry should know some things about where superconductivity may lead us and must consider whether the greater risk is to develop them or to let others try it. There are no easy answers yet.

Smith, J.L.

1987-01-01T23:59:59.000Z

477

Fabrication and characterization of aluminum airbridges for superconducting microwave circuits  

SciTech Connect (OSTI)

Superconducting microwave circuits based on coplanar waveguides (CPW) are susceptible to parasitic slotline modes which can lead to loss and decoherence. We motivate the use of superconducting airbridges as a reliable method for preventing the propagation of these modes. We describe the fabrication of these airbridges on superconducting resonators, which we use to measure the loss due to placing airbridges over CPW lines. We find that the additional loss at single photon levels is small, and decreases at higher drive powers.

Chen, Zijun; Kelly, J.; Barends, R.; Bochmann, J.; Chen, Yu; Chiaro, B.; Dunsworth, A.; Jeffrey, E.; Mutus, J. Y.; O'Malley, P. J. J.; Neill, C.; Roushan, P.; Sank, D.; Vainsencher, A.; Wenner, J.; White, T. C. [Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States); Megrant, A. [Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States); Department of Materials, University of California, Santa Barbara, California 93106 (United States); Cleland, A. N.; Martinis, John M., E-mail: martinis@physics.ucsb.edu [Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States); California NanoSystems Institute, University of California, Santa Barbara, California 93106-9530 (United States)

2014-02-03T23:59:59.000Z

478

High temperature superconductivity in metallic region near Mott transition  

E-Print Network [OSTI]

The spin-singlet superconductivity without phonons is examined in consideration of correlations on an extended Hubbard model. It is shown that the superconductivity requires not only the total correlation should be strong enough but also the density of state around Fermi energy should be large enough, which shows that the high temperature superconductivity could only be found in the metallic region near the Mott metal insulator transition (MIT). Other properties of superconductors are also discussed on these conclusions.

Tian De Cao

2009-09-11T23:59:59.000Z

479

Substrates suitable for deposition of superconducting thin films  

DOE Patents [OSTI]

A superconducting system for the lossless transmission of electrical current comprising a thin film of superconducting material Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x epitaxially deposited upon a KTaO.sub.3 substrate. The KTaO.sub.3 is an improved substrate over those of the prior art since the it exhibits small lattice constant mismatch and does not chemically react with the superconducting film.

Feenstra, Roeland (Oak Ridge, TN); Boatner, Lynn A. (Oak Ridge, TN)

1993-01-01T23:59:59.000Z

480

Method for manufacturing a rotor having superconducting coils  

DOE Patents [OSTI]

A method and apparatus for manufacturing a rotor for use with a rotating machine is provided that employs a superconducting coil on the rotor. An adhesive is applied to an outer surface of the rotor body, which may include a groove disposed within an outer surface of the rotor body. A superconducting coil is then mounted onto the rotor body such that the adhesive bonds the superconducting coil to the rotor body.

Driscoll, David I. (South Euclid, OH); Shoykhet, Boris A. (Beachwood, OH)

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nanofabricated superconducting rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Magnetism and superconductivity in quark matter  

E-Print Network [OSTI]

Magnetic properties of quark matter and its relation to the microscopic origin of the magnetic field observed in compact stars are studied. Spontaneous spin polarization appears in high-density region due to the Fock exchange term, which may provide a scenario for the behaviors of magnetars. On the other hand, quark matter becomes unstable to form spin density wave in the moderate density region, where restoration of chiral symmetry plays an important role. Coexistence of magnetism and color superconductivity is also discussed.

T. Tatsumi; E. Nakano; K. Nawa

2005-06-01T23:59:59.000Z

482

On a Model of Superconductivity and Biology  

E-Print Network [OSTI]

The paper deals with a semilinear integrodifferential equation that characterizes several dissipative models of Viscoelasticity, Biology and Superconductivity. The initial - boundary problem with Neumann conditions is analyzed. When the source term F is a linear function, then the explicit solution is obtained. When F is non linear, some results on existence, uniqueness and a priori estimates are deduced. As example of physical model the reaction - diffusion system of Fitzhugh Nagumo is considered.

Monica De Angelis

2012-03-02T23:59:59.000Z

483

Dual superconducting properties of the QCD vacuum  

E-Print Network [OSTI]

A consistent description of the confining QCD vacuum as a dual superconductor requires a determination of fundamental parameters such as the superconductor correlation length $\\xi$ and the field penetration depth $\\lambda$, which determine whether the superconductor is of type I or type II. We illustrate preliminary results of a lattice determination of $\\xi$ for the case of pure Yang-Mills with two colors, obtained by measuring the temporal correlator of a disorder parameter detecting dual superconductivity.

A. D'Alessandro; M. D'Elia

2005-10-27T23:59:59.000Z

484

Rotor assembly including superconducting magnetic coil  

DOE Patents [OSTI]

Superconducting coils and methods of manufacture include a superconductor tape wound concentrically about and disposed along an axis of the coil to define an opening having a dimension which gradually decreases, in the direction along the axis, from a first end to a second end of the coil. Each turn of the superconductor tape has a broad surface maintained substantially parallel to the axis of the coil.

Snitchler, Gregory L. (Shrewsbury, MA); Gamble, Bruce B. (Wellesley, MA); Voccio, John P. (Somerville, MA)

2003-01-01T23:59:59.000Z

485

Holographic Superconductivity with Gauss-Bonnet gravity  

E-Print Network [OSTI]

I review recent work on holographic superconductivity with Einstein-Gauss-Bonnet gravity, and show how the critical temperature of the superconductor depends on both gravitational backreaction and the Gauss-Bonnet parameter, using both analytic and numerical arguments. I also review computations of the conductivity, finding the energy gap, and demonstrating that there is no universal gap ratio, $\\omega_g/T_c$, for these superconductors.

Ruth Gregory

2010-12-07T23:59:59.000Z

486

Quantum Heat Engines Using Superconducting Quantum Circuits  

E-Print Network [OSTI]

We propose a quantum analog of the internal combustion engine used in most cars. Specifically, we study how to implement the Otto-type quantum heat engine (QHE) with the assistance of a Maxwell's demon. Three steps are required: thermalization, quantum measurement, and quantum feedback controlled by the Maxwell demon. We derive the positive-work condition of this composite QHE. Our QHE can be constructed using superconducting quantum circuits. We explicitly demonstrate the essential role of the demon in this macroscopic QHE.

H. T. Quan; Y. D. Wang; Yu-xi Liu; C. P. Sun; Franco Nori

2006-09-14T23:59:59.000Z

487

Production and decay properties of the 1.9-s isomeric state in {sup 261}Rf  

SciTech Connect (OSTI)

The 1.9-s isomeric state ({sup 261}Rf{sup b}) in {sup 261}Rf was directly populated in the {sup 248}Cm({sup 18}O,5n){sup 261}Rf{sup b} reaction. Alpha and spontaneous fission (SF) decays of {sup 261}Rf{sup b}, as well as the 68-s state {sup 261}Rf{sup a}, was investigated with a rotating wheel apparatus under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. An identification of {sup 261}Rf{sup b} was based on {alpha}-{alpha} correlations linking {alpha} decays of {sup 261}Rf{sup b} and its daughter {sup 257}No. The {alpha}-particle energy of {sup 261}Rf{sup b} was measured to be 8.52 {+-} 0.05 MeV. The half-life was determined to be 1.9 {+-} 0.4 s based on both 8.52-MeV {alpha} and SF decays. The {alpha} and SF branches are 0.27 {+-} 0.06 and 0.73 {+-} 0.06, respectively. The cross section for the {sup 248}Cm({sup 18}O,5n){sup 261}Rf{sup b} reaction is {sigma}({sup 261}Rf{sup b}) = 11 {+-} 2 nb at 95.1 MeV, which gives a cross-section ratio of {sigma}({sup 261}Rf{sup a})/{sigma}({sup 261}Rf{sup b}) = 1.1 {+-} 0.2.

Haba, H.; Kaji, D.; Kikunaga, H.; Kudou, Y.; Morimoto, K.; Morita, K.; Ozeki, K.; Sumita, T.; Yoneda, A.; Kasamatsu, Y.; Komori, Y.; Ooe, K.; Shinohara, A. [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

2011-03-15T23:59:59.000Z

488

New SLED 3 system for Multi-mega Watt RF compressor  

E-Print Network [OSTI]

A compact X band SLED is introduced for X band RF compressing application. This SLED compressor consists two major parts: a rectangular to circular waveguide converter and an overmoded spherical cavity. The RF compressor is designed to convert 50 magawatt X band RF power with pulse length 1.5 microseconds and deliver 200 megawatts with pulse length 106 nanoseconds to the X band accelerating structure.

Xu, Chen; Tantawi, Sami

2014-01-01T23:59:59.000Z

489

Ultrananocrystalline diamond films with optimized dielectric properties for advanced RF MEMS capacitive switches  

DOE Patents [OSTI]

An efficient deposition process is provided for fabricating reliable RF MEMS capacitive switches with multilayer ultrananocrystalline (UNCD) films for more rapid recovery, charging and discharging that is effective for more than a billion cycles of operation. Significantly, the deposition process is compatible for integration with CMOS electronics and thereby can provide monolithically integrated RF MEMS capacitive switches for use with CMOS electronic devices, such as for insertion into phase array antennas for radars and other RF communication systems.

Sumant, Anirudha V.; Auciello, Orlando H.; Mancini, Derrick C.

2013-01-15T23:59:59.000Z

490

Superconductivity in Zigzag CuO Chains  

SciTech Connect (OSTI)

Superconductivity has recently been discovered in Pr{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15-{delta}} with a maximum T{sub c} of about 15K. Since the CuO planes in this material are believed to be insulating, it has been proposed that the superconductivity occurs in the double (or zigzag) CuO chain layer. On phenomenological grounds we propose a theoretical interpretation of the experimental results in terms of a new phase for the zigzag chain, labelled by C{sub 1}S{sub 3/2}. This phase has a gap in the relative charge mode and a partial gap in the relative spin mode. It has gapless uniform charge and spin excitations and can have a divergent superconducting susceptibility, even for repulsive interactions. A microscopic model for the zigzag CuO chain is proposed, and on the basis of density matrix renormalization group (DMRG) and bosonization studies, we adduce evidence that supports our proposal.

Berg, E.

2010-04-06T23:59:59.000Z

491

Magnetar superconductivity versus magnetism: neutrino cooling processes  

E-Print Network [OSTI]

We describe the microphysics, phenomenology, and astrophysical implication of a $B$-field induced unpairing effect that may occur in magnetars, if the local $B$-field in the core of a magnetar exceeds a critical value $H_{c2}$. Using the Ginzburg-Landau (GL) theory of superconductivity, we derive the $H_{c2}$ field for proton condensate taking into the correction ($\\le 30\\%$) which arises from its coupling to the background neutron condensate. The density dependence of pairing of proton condensate implies that $H_{c2}$ is maximal at the crust-core interface and decreases towards the center of the star. As a consequence, magnetar cores with homogenous constant fields will be partially superconducting for "medium-field" magnetars ($10^{15}\\le B\\le 5 \\times 10^{16}$ G) whereas "strong-field" magnetars ($B>5\\times 10^{16}$ G) will be void of superconductivity. The emissivity of a magnetar's core changes in twofold manner: (i)~the $B$-field assisted direct Urca process is enhanced by orders of magnitude, because o...

Sinha, Monika

2015-01-01T23:59:59.000Z

492

Color superconducting quark matter in compact stars  

E-Print Network [OSTI]

Recent indications for high neutron star masses (M \\sim 2 M_sun) and large radii (R > 12 km) could rule out soft equations of state and have provoked a debate whether the occurence of quark matter in compact stars can be excluded as well. We show that modern quantum field theoretical approaches to quark matter including color superconductivity and a vector meanfield allow a microscopic description of hybrid stars which fulfill the new, strong constraints. For these objects color superconductivity turns out to be an essential ingredient for a successful description of the cooling phenomenology in accordance with recently developed tests. We discuss the energy release in the neutrino untrapping transition as a new aspect of the problem that hybrid stars masquerade themselves as neutron stars. Quark matter searches in future generations of low-temperature/high-density nucleus-nucleus collision experiments such as low-energy RHIC and CBM @ FAIR might face the same problem of an almost crossover behavior of the deconfinement transition. Therefore, diagnostic tools shall be derived from effects of color superconductivity.

D. B. Blaschke; T. Klahn; F. Sandin

2007-12-02T23:59:59.000Z

493

Superconductivity for Electric Systems: 2008 Annual Peer Review...  

Broader source: Energy.gov (indexed) [DOE]

for Electric Systems: 2008 Annual Peer Review Final Report Superconductivity for Electric Systems: 2008 Annual Peer Review Final Report The Office of Electricity Delivery and...

494

Damping and support in high-temperature superconducting levitation systems  

DOE Patents [OSTI]

Methods and apparatuses to provide improved auxiliary damping for superconducting bearings in superconducting levitation systems are disclosed. In a superconducting bearing, a cryostat housing the superconductors is connected to a ground state with a combination of a damping strip of material, a set of linkage arms to provide vertical support, and spring washers to provide stiffness. Alternately, the superconducting bearing may be supported by a cryostat connected to a ground state by posts constructed from a mesh of fibers, with the damping and stiffness controlled by the fiber composition, size, and mesh geometry.

Hull, John R. (Sammamish, WA); McIver, Carl R. (Everett, WA); Mittleider, John A. (Kent, WA)

2009-12-15T23:59:59.000Z

495

Type-I superconductivity and neutron star precession  

E-Print Network [OSTI]

Type-I proton superconducting cores of neutron stars break up in a magnetic field into alternating domains of superconducting and normal fluids. We examine two channels of superfluid-normal fluid friction where (i) rotational vortices are decoupled from the non-superconducting domains and the interaction is due to the strong force between protons and neutrons; (ii) the non-superconducting domains are dynamically coupled to the vortices and the vortex motion generates transverse electric fields within them, causing electronic current flow and Ohmic dissipation. The obtained dissipation coefficients are consistent with the Eulerian precession.

Armen Sedrakian

2005-03-30T23:59:59.000Z

496

Robust manipulation of superconducting qubits in the presence of fluctuations  

E-Print Network [OSTI]

Superconducting quantum systems are promising candidates for quantum information processing due to their scalability and design flexibility. However, the existence of defects, fluctuations, and inaccuracies is unavoidable for practical superconducting quantum circuits. In this paper, a sampling-based learning control (SLC) method is used to guide the design of control fields for manipulating superconducting quantum systems. Numerical results for one-qubit systems and coupled two-qubit systems show that the "smart" fields learned using the SLC method can achieve robust manipulation of superconducting qubits even in the presence of large fluctuations and inaccuracies.

Daoyi Dong; Chunlin Chen; Bo Qi; Ian R. Petersen; Franco Nori

2014-08-07T23:59:59.000Z

497

ac superconducting power: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Z. Hong, Y. Yan, R. Pei, Y. Jiang and T. A. Coombs, Design... and test of a Superconduct- ing Magnetic Energy Storage (SMES) coil, IEEE transaction on applied...

498

amorphous wc superconducting: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: alloy of composition correspond- ing to the metallic components of the superconduct- ing oxides respectivement. Abstract. - Previous quenching experiments on 2212...

499

Magnetism and superconductivi[t]y in Pr-based filled skutterudite arsenides  

E-Print Network [OSTI]

1.5 Superconductivity . . . . . . . . . . . . . . . . . . .and M. B. Maple, ”Superconductivity and non-Fermi liquidSAN DIEGO Magnetism and Superconductiviy in Pr-based Filled

Sayles, Todd Allen

2008-01-01T23:59:59.000Z

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E-Print Network 3.0 - aluminum-stabilized superconducting cables...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

New superconducting technology will help America reduce the demand for additional electric power Summary: ,000-amp, 3-phase superconducting cable at American Electric Power's...