Search results for "High temperature superconductors"

showing 4 items of 4 documents

Surface-barrier effects in the microwave second-harmonic response of superconductors in the mixed state

2005

We report on transient effects in the microwave second-harmonic response of different type of superconductors in the mixed state. The samples have contemporarily been exposed to a dc magnetic field, varying with a constant rate of 60 Oe/s, and a pulsed microwave magnetic field. The time evolution of the signal radiated at the second-harmonic frequency of the driving field has been measured for about 500 s from the instant in which the dc-field sweep has been stopped, with sampling time of ∼0.3 s. We show that the second-harmonic signal exhibits two relaxation regimes; an initial exponential decay, which endures roughly 10 s, and a logarithmic decay in the time scale of minutes. Evidence is …

SuperconductivityMaterials scienceHigh temperature superconductors Vortex flow circuit modelCondensed matter physicsField (physics)Relaxation (NMR)Time evolutionTransient (oscillation)Exponential decayCondensed Matter PhysicsMicrowaveElectronic Optical and Magnetic MaterialsMagnetic fieldThe European Physical Journal B
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Magnetic hysteresis in the microwave surface resistance of Nb samples in the critical state

2006

We discuss the hysteretic behavior of the field-induced variations of the microwave surface resistance in superconductors in the critical state. Measurements have been performed in a bulk sample of Nb and a powdered one at different values of the temperature. We discuss a model, based on the Coffey and Clem theory, in which we take into account the flux distribution inside the sample, due to the critical state. The experimental results are justified quantitatively in the framework of our model. We show that by fitting the experimental data it is possible to determine the value of the critical current density and its field dependence.

Superconductivitycircuit modelCondensed Matter - Materials ScienceMicrowave surface resistanceFlux distributionMaterials scienceCondensed matter physicsCondensed Matter - SuperconductivityVortex flowMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesField dependenceHigh temperature superconductorsCondensed Matter PhysicsMagnetic hysteresisElectronic Optical and Magnetic MaterialsSuperconductivity (cond-mat.supr-con)Condensed Matter::SuperconductivityCritical current
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The magnet of the scattering and neutrino detector for the SHiP experiment at CERN

2019

The Search for Hidden Particles (SHiP) experiment proposal at CERN demands a dedicated dipole magnet for its scattering and neutrino detector. This requires a very large volume to be uniformly magnetized at B > 1.2 T, with constraints regarding the inner instrumented volume as well as the external region, where no massive structures are allowed and only an extremely low stray field is admitted. In this paper we report the main technical challenges and the relevant design options providing a comprehensive design for the magnet of the SHiP Scattering and Neutrino Detector.

TechnologyPhysics - Instrumentation and Detectorswigglers and undulators)magnet: designPermanent magnet devicesPhysics::Instrumentation and Detectorsengineering01 natural sciences7. Clean energy09 Engineering030218 nuclear medicine & medical imagingradiation hardened magnetsSubatomär fysik0302 clinical medicineDipole magnetSubatomic PhysicsNeutrino detectorsDetectors and Experimental TechniquesInstruments & InstrumentationInstrumentationphysics.ins-detAcceleration cavities and magnets superconducting (high-temperature superconductor; radiation hardened magnets; normal-conducting; permanent magnet devices; wigglers and undulators)Mathematical PhysicsPhysics02 Physical SciencesLarge Hadron ColliderInstrumentation and Detectors (physics.ins-det)magnet: technologyNuclear & Particles Physicsbending magnetneutrino: detectorNeutrino detectornormal-conductingAcceleration cavities and magnets superconducting (high-temperature superconductorproposed experimentCERN LabRadiation hardened magnetsFOS: Physical sciencesNormal-conductingAccelerator Physics and InstrumentationNuclear physics03 medical and health sciences0103 physical sciencespermanent magnet devices[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]Wigglers and undulators)normal-conducting magnetsScience & Technology010308 nuclear & particles physicsScatteringLarge detector systems for particle and astroparticle physicsAcceleratorfysik och instrumenteringLarge detector systems for particle physicsHigh temperature superconductors Neutrons Permanent magnets Ships Superconducting magnets Wigglers Astroparticle physics Comprehensive designs Massive structures Neutrino detectors Normal-conducting Radiation-hardened Ship experiments Technical challenges Particle detectorsVolume (thermodynamics)MagnetAcceleration cavities and magnets superconducting (high-temperature superconductor; Large detector systems for particle and astroparticle physics; Neutrino detectors; Normal-conducting; Permanent magnet devices; Radiation hardened magnets; Wigglers and undulators)High Energy Physics::Experimentneutrino detectors
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Critical-state effects on microwave losses in type-II superconductors

2006

We discuss the microwave energy losses in superconductors in the critical state. The field-induced variations of the surface resistance are determined, in the framework of the Coffey and Clem model, by taking into account the distribution of the vortex magnetic field inside the sample. It is shown that the effects of the critical state cannot generally be disregarded to account for the experimental data. Results obtained in bulk niobium at low temperatures are quantitatively justified.

circuit modelSuperconductivityMaterials scienceCondensed matter physicsCondensed Matter - SuperconductivityVortex flowNiobiumFOS: Physical scienceschemistry.chemical_elementHigh temperature superconductorsCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsMagnetic fieldVortexSuperconductivity (cond-mat.supr-con)chemistryCondensed Matter::SuperconductivityType-II superconductorMicrowaveSheet resistanceThe European Physical Journal B - Condensed Matter and Complex Systems
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