Search results for "MAGNETIC FIELD"

showing 10 items of 1488 documents

Effective-Lagrangian formulation of generalized vector dominance. II

1975

As in a preceding paper we generalize the Lagrangian of Lee and Zumino to include several mutually interacting vector mesons. The treatment is more general in the sense that all possible interactions between the vector mesons, compatible with the field-current proportionality relations, are now discussed. It is moreover demonstrated that also the fields corresponding to the physical vector mesons satisfy a field-current proportionality relation of exactly the same form. Comparison of the different schemes and their implications for the magnetic moments of the vector mesons are discussed.

Coupling constantElectromagnetic fieldPhysicsMagnetic momentMesonHigh Energy Physics::LatticeNuclear TheoryCurrent algebraProportionality (mathematics)Quantum mechanicsEffective lagrangianHigh Energy Physics::ExperimentVector potentialMathematical physicsPhysical Review D
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Refined equivalent single layer formulations and finite elements for smart laminates free vibrations

2014

A family of 2D refined equivalent single layer models for multilayered and functionally graded smart magneto-electro-elastic plates is presented. They are based on variable kinematics and quasi-static behavior for the electromagnetic fields. First, the electromagnetic state of the plate is determined by solving the strong form of the electromagnetic governing equations coupled with the corresponding interface continuity conditions and external boundary conditions. The electromagnetic state is then condensed into the plate kinematics, whose governing equations can be written using the generalized principle of virtual displacements. The procedure identifies an effective elastic plate kinemati…

CouplingElectromagnetic fieldMaterials scienceMechanical Engineeringmedia_common.quotation_subjectConstitutive equationStiffnessComputational modelingInertiaSmart materialSmart laminatesIndustrial and Manufacturing EngineeringFinite element methodLaminate mechanicMechanics of MaterialsCeramics and CompositesmedicineBoundary value problemmedicine.symptomComposite materialSettore ING-IND/04 - Costruzioni E Strutture Aerospazialimedia_common
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Topological edge states of nonequilibrium polaritons in hollow honeycomb arrays

2020

We address topological currents in polariton condensates excited by uniform resonant pumps in finite honeycomb arrays of microcavity pillars with a hole in the center. Such currents arise under combined action of the spin–orbit coupling and Zeeman splitting, which breaks the time-reversal symmetry and opens a topological gap in the spectrum of the structure. The most representative feature of this structure is the presence of two interfaces, inner and outer ones, where the directions of topological currents are opposite. Due to the finite size of the structure, polariton–polariton interactions lead to coupling of the edge states at the inner and outer interfaces, which depends on the size o…

CouplingPhysicsCondensed Matter::Quantum GasesZeeman effectBistabilityHoneycomb (geometry)FOS: Physical sciencesPhysics::Optics02 engineering and technology021001 nanoscience & nanotechnologyTopology01 natural sciencesAtomic and Molecular Physics and OpticsSymmetry (physics)Magnetic field010309 opticssymbols.namesake0103 physical sciencesPolaritonsymbols0210 nano-technologyPhotonic crystalOptics (physics.optics)Physics - Optics
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Array of planar Penning traps as a nuclear magnetic resonance molecule for quantum computation

2005

An array of planar Penning traps, holding single electrons, can realize an artificial molecule suitable for NMR-like quantum information processing. The effective spin-spin coupling is accomplished by applying a magnetic field gradient, combined to the Coulomb interaction acting between the charged particles. The system lends itself to scalability, since the same substrate can easily accommodate an arbitrary number of traps. Moreover, the coupling strength is tunable and under experimental control. Our theoretical predictions take into account a realistic setting, within the reach of current technology.

CouplingPhysicsQuantum PhysicsFOS: Physical sciencesElectronPenning trapAtomic and Molecular Physics and OpticsCharged particleMagnetic fieldNuclear magnetic resonancePlanarAtomic physicsQuantum informationQuantum Physics (quant-ph)Quantum computerPhysical Review A
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Investigation of the magnetic field fluctuation and implementation of a temperature and pressure stabilization at SHIPTRAP

2011

Abstract Penning traps have proven to be powerful tools for the determination of nuclear masses with high accuracy. A crucial parameter for precision mass measurements in Penning traps is the accurate determination of the magnetic-field strength. However, the magnetic field of a superconducting magnet is not constant in time, but changes due to intrinsic effects of the solenoid and external perturbations. These effects have been investigated for SHIPTRAP. Furthermore, a stabilization of the temperature in the magnet bore as well as of the pressure in the liquid-helium cryostat has been implemented. Thus, the magnetic-field related uncertainties have been reduced to 7(6)×10−11/h.

CryostatPhysicsNuclear and High Energy PhysicsCondensed matter physicsPressure stabilizationSolenoidSuperconducting magnetPenning trapMagnetic fieldTemperature and pressureMagnetPhysics::Atomic PhysicsAtomic physicsInstrumentationNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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Magnetic alignment of aliphatic lamellae

1993

Abstract Magnetic alignment of mesophases is normally only considered possible when the molecule contains an aromatic ring system. In this paper we report on the mesomorphous behaviour of a polyalkylacrylate resin with average sidechain length 22 and the alignment of its lamellae in cast films by annealing in a strong magnetic field.

CrystallographyNuclear magnetic resonanceAnnealing (metallurgy)ChemistryMaterials ChemistryMetals and AlloysMoleculeSurfaces and InterfacesCast filmsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsMagnetic fieldThin Solid Films
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Mixed spin-state [HS-LS] pairs in a dinuclear spin-transition complex: confirmation by variable-temperature 57Fe Mössbauer spectroscopy.

2008

Exquisite sensitivity of Mossbauer spectroscopy for tiny local molecular distortion is demonstrated in [FeII2(pmat)2](BF4)4?DMF: high-spin (HS) iron(II) in [HS-HS] and in [LS-HS] (low-spin–high-spin) pairs is clearly distinguished (see picture) for the first time without the need to apply a magnetic field. This dinuclear complex clearly shows that spin crossover via a [LS-HS] species is promoted by the use of a highly constrained bridging ligand (the bis-terdentate pmat).

CrystallographySpin statesSpin crossoverChemistryMössbauer spectroscopySpin transitionAnalytical chemistryBridging ligandGeneral MedicineGeneral ChemistryCatalysisMagnetic fieldAngewandte Chemie (International ed. in English)
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Modification of Dzyaloshinskii-Moriya-Interaction-Stabilized Domain Wall Chirality by Driving Currents

2018

We measure and analyze the chirality of Dzyaloshinskii-Moriya-interaction (DMI) stabilized spin textures in multilayers of $\mathrm{Ta}|{\mathrm{Co}}_{20}{\mathrm{F}}_{60}{\mathrm{B}}_{20}|\mathrm{MgO}$. The effective DMI is measured experimentally using domain wall motion measurements, both in the presence (using spin-orbit torques) and absence of driving currents (using magnetic fields). We observe that the current-induced domain wall motion yields a change in effective DMI magnitude and opposite domain wall chirality when compared to field-induced domain wall motion (without current). We explore this effect, which we refer to as current-induced DMI, by providing possible explanations for…

Current (mathematics)Current-inducedGeneral Physics and AstronomyFOS: Physical sciencesSpin currents02 engineering and technology-01 natural sciencesMeasure (mathematics)Spin current0103 physical sciencesMesoscale and Nanoscale Physics (cond-mat.mes-hall)ddc:55022 Física010306 general physicsDomain Wall ChiralitySpin-½PhysicsCondensed matter physicsfísicaCondensed Matter - Mesoscale and Nanoscale PhysicsTheoretical predictionsPhysics021001 nanoscience & nanotechnologyMagnetic fieldDomain wall (magnetism)Dzyaloshinskii-Moriya-interaction (DMI)0210 nano-technologyChirality (chemistry)Field-induced domainDzyaloshinskii-Moriya-interaction
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Nondiverging vortex pinning barriers at low current densities across the putative elastic vortex-glass–vortex-liquid transition inYBa2Cu3O7−δfilms

2001

A detailed analysis of the electric field--current density $(E\ensuremath{-}J)$ characteristics of ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ films across the putative thermally induced elastic vortex-glass--vortex-liquid transition predicted by the $E(J)$ curve scaling reveals that the expected increase of the collective pinning barriers with decreasing J is cut off in the low-$J$ region, signaling a dissipation process which involves the plastic deformation of the vortex system. The temperature and magnetic field dependence of the pinning barriers at low J does not change across the scaling-predicted glass transition line. For the investigated m…

Current (mathematics)Materials scienceCondensed matter physicsCondensed Matter::SuperconductivityGlass transitionPinning forceScalingVortexMagnetic fieldLine (formation)Physical Review B
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Pulsed electromagnetic field therapy in the treatment of pain and other symptoms in fibromyalgia : a randomized controlled study

2018

Low-energy pulsed electromagnetic field (PEMF) therapy has been suggested as a promising therapy to increase microcirculation, which is of great concern in patients with fibromyalgia. This study evaluated the effectiveness of PEMF therapy on the treatment of fibromyalgia. A group of 108 women with fibromyalgia were allocated to a 12-week treatment period with an active Bio-Electro-Magnetic-Energy-Regulation (BEMER) device and a similar treatment period with an inactive device. Each patient received active and sham treatments in a random order. Pain and stiffness were assessed on a visual analog scale (VAS, scale 0-100mm), and functional status was assessed by the Fibromyalgia Impact Questio…

DISORDERSsähkömagneettiset kentätsham treatmentWOMENmicrocirculationpulsed electromagnetic fieldmagneettihoitoCONTROLLED-TRIALEFFICACYverenkiertoDISEASEELECTRICAL NERVE-STIMULATIONIMPACT QUESTIONNAIRECLINICAL-TRIALkivunhoitoDOUBLE-BLINDINFLAMMATIONkrooninen kipufibromyalgia3111 Biomedicinechronic painmagnetotherapy
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