scholarly journals High-Frequency Electromagnetic Emission from Non-Local Wavefunctions

2019 ◽  
Vol 9 (10) ◽  
pp. 1982 ◽  
Author(s):  
Giovanni Modanese
Keyword(s):  
Electromagnetic Emission ◽  
Longitudinal Component ◽  
Transverse Component ◽  
Local Part ◽  
Invariant Current ◽  
Josephson Tunnelling ◽  
Yttrium Barium ◽  
Non Local ◽  
Source Dipole ◽  
Aharonov Bohm

In systems with non-local potentials or other kinds of non-locality, the Landauer-Büttiker formula of quantum transport leads to replacing the usual gauge-invariant current density J with a current J e x t which has a non-local part and coincides with the current of the extended Aharonov-Bohm electrodynamics. It follows that the electromagnetic field generated by this current can have some peculiar properties and in particular the electric field of an oscillating dipole can have a long-range longitudinal component. The calculation is complex because it requires the evaluation of double-retarded integrals. We report the outcome of some numerical integrations with specific parameters for the source: dipole length ∼10−7 cm, frequency 10 GHz. The resulting longitudinal field E L turns out to be of the order of 10 2 to 10 3 times larger than the transverse component (only for the non-local part of the current). Possible applications concern the radiation field generated by Josephson tunnelling in thick superconductor-normal-superconductor (SNS) junctions in yttrium barium oxide (YBCO) and by current flow in molecular nanodevices.

scholarly journals Longitudinal Component Properties of Circularly Polarized Terahertz Vortex Beams

2021 ◽  
Vol 9 ◽  
Author(s):  
Miao Wang ◽  
Xinke Wang ◽  
Peng Han ◽  
Wenfeng Sun ◽  
Shengfei Feng ◽  
...  
Keyword(s):  
Spot Size ◽  
Longitudinal Component ◽  
Transverse Component ◽  
Quarter Wave Plate ◽  
Phase Plate ◽  
Vortex Beam ◽  
Circularly Polarized ◽  
Left Hand ◽  
Quarter Wave ◽  
Focusing Properties

A circularly polarized vortex beam possesses similar focusing properties as a radially polarized beam. This type of beam is highly valuable for developing optical manufacturing technology, microscopy, and particle manipulation. In this work, a left-hand circularly polarized terahertz (THz) vortex beam (CPTVB) is generated by utilizing a THz quarter wave plate and a spiral phase plate. Focusing properties of its longitudinal component Ez are detailedly discussed on the simulation and experiment. With reducing the F-number of the THz beam and comparing with a transverse component Ex of a general circularly polarized THz beam, the simulation results show that the focal spot size and intensity of its Ez component can reach 87 and 50% of Ex under a same focusing condition. In addition, the experimental results still demonstrate that the left-hand CPTVB can always maintain fine Ez focusing properties in a broad bandwidth, which manifest the feasibility of this class of THz beams.

scholarly journals Classification of bi-Hamiltonian pairs extended by isometries

2021 ◽  
Vol 477 (2251) ◽  
pp. 20210185
Author(s):  
Maxim V. Pavlov ◽  
Pierandrea Vergallo ◽  
Raffaele Vitolo
Keyword(s):  
Type System ◽  
Local Part ◽  
First Order ◽  
Hydrodynamic Type System ◽  
Dependent Variables ◽  
Particular Solution ◽  
Non Local ◽  
Hamiltonian Operators ◽  
Hamiltonian Pair

The aim of this article is to classify pairs of the first-order Hamiltonian operators of Dubrovin–Novikov type such that one of them has a non-local part defined by an isometry of its leading coefficient. An example of such a bi-Hamiltonian pair was recently found for the constant astigmatism equation. We obtain a classification in the case of two dependent variables, and a significant new example with three dependent variables that is an extension of a hydrodynamic-type system obtained from a particular solution of the Witten–Dijkgraaf–Verlinde–Verlinde equations.

scholarly journals A Non-Local Action for Electrodynamics: Duality Symmetry and the Aharonov-Bohm Effect, Revisited

Symmetry ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1191 ◽  
Author(s):  
Joan Bernabeu ◽  
Jose Navarro-Salas
Keyword(s):  
Electromagnetic Field ◽  
Magnetic Fields ◽  
Harmonic Oscillator ◽  
Local Action ◽  
Action Functional ◽  
Duality Symmetry ◽  
Electric And Magnetic Fields ◽  
Non Local ◽  
Bohm Effect ◽  
Aharonov Bohm

A non-local action functional for electrodynamics depending on the electric and magnetic fields, instead of potentials, has been proposed in the literature. In this work we elaborate and improve this proposal. We also use this formalism to confront the electric-magnetic duality symmetry of the electromagnetic field and the Aharonov–Bohm effect, two subtle aspects of electrodynamics that we examine in a novel way. We show how the former can be derived from the simple harmonic oscillator character of vacuum electrodynamics, while also demonstrating how the magnetic version of the latter naturally arises in an explicitly non-local manner.

The propagation of magneto-thermo-viscoelastic plane waves in a parallel union of the Kelvin and Maxwell bodies

1971 ◽  
Vol 70 (2) ◽  
pp. 343-350 ◽  
Author(s):  
D. S. Chandrasekhariah
Keyword(s):  
Magnetic Field ◽  
Electrical Conductivity ◽  
Electromagnetic Field ◽  
Wave Propagation ◽  
Thermal Field ◽  
Plane Waves ◽  
Viscoelastic Body ◽  
Longitudinal Component ◽  
Transverse Component ◽  
Wave Travel

AbstractThe propagation of plane waves in a viscoelastic body representing a parallel union of the Kelvin and Maxwell bodies placed in a magneto-thermal field is investigated. It is shown that the longitudinal component of the wave is in general coupled with a transverse component and the wave travels in two families. In particular if the primary magnetic field is either parallel or perpendicular to the direction of wave propagation, the three components of the wave travel unlinked, with either the longitudinal component or the transverse components unaffected by the presence of the electromagnetic field. If the electrical conductivity of the solid is infinite the effect of the primary magnetic field is to increase the values of the material constants. The effect of wave propagation on magnetic permeability is equivalent to an anisotropic rescaling of the primary magnetic field. Some of the results obtained in the earlier works are obtained as particular cases of the more general results derived here.

scholarly journals A Computational Method for Analyzing the Biomechanics of Arterial Bruits

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Chi Zhu ◽  
Jung-Hee Seo ◽  
Hani Bakhshaee ◽  
Rajat Mittal
Keyword(s):  
Shear Wave ◽  
Sound Propagation ◽  
Acoustic Method ◽  
Longitudinal Component ◽  
Transverse Component ◽  
Computational Method ◽  
Surrounding Tissue ◽  
Immersed Boundary ◽  
Flow Solver ◽  
Epidermal Surface

A computational framework consisting of a one-way coupled hemodynamic–acoustic method and a wave-decomposition based postprocessing approach is developed to investigate the biomechanics of arterial bruits. This framework is then applied for studying the effect of the shear wave on the generation and propagation of bruits from a modeled stenosed artery. The blood flow in the artery is solved by an immersed boundary method (IBM) based incompressible flow solver. The sound generation and propagation in the blood volume are modeled by the linearized perturbed compressible equations, while the sound propagation through the surrounding tissue is modeled by the linear elastic wave equation. A decomposition method is employed to separate the acoustic signal into a compression/longitudinal component (curl free) and a shear/transverse component (divergence free), and the sound signals from cases with and without the shear modulus are monitored on the epidermal surface and are analyzed to reveal the influence of the shear wave. The results show that the compression wave dominates the detected sound signal in the immediate vicinity of the stenosis, whereas the shear wave has more influence on surface signals further downstream of the stenosis. The implications of these results on cardiac auscultation are discussed.

Wavelet analyses of velocities in laboratory isotropic turbulence

1999 ◽  
Vol 389 ◽  
pp. 229-254 ◽  
Author(s):  
H. MOURI ◽  
H. KUBOTANI ◽  
T. FUJITANI ◽  
H. NIINO ◽  
M. TAKAOKA
Keyword(s):  
Wavelet Transforms ◽  
Isotropic Turbulence ◽  
Longitudinal Component ◽  
Transverse Component ◽  
Small Scale ◽  
Grid Turbulence ◽  
Spatial Fluctuation ◽  
Analysis Techniques ◽  
Velocity Increments ◽  
Wavelet Analyses

Orthonormal wavelet transformations are used to decompose velocity signals of grid turbulence into both space and scale. The transforms exhibit small-scale enhancements of (i) the spatial fluctuation, (ii) the correlation in space between the adjacent scales, and (iii) the correlation in space between the longitudinal and transverse components. The spatial fluctuation and the scale–scale correlation at small scales are more significant in the transverse component than in the longitudinal component. These features are the same for different families of wavelets.Turbulence contains tube-like structures of vorticity. We demonstrate that wavelet transforms of velocities are enhanced at the positions of the tubes, by using a direct numerical simulation. Thus our wavelet analyses have captured the effects of those coherent structures on velocities measured in the experiment, which would be difficult for traditional analysis techniques such as those with velocity increments.

Vector light fields

Optics f2f ◽  
2018 ◽  
pp. 195-212
Author(s):  
Charles S. Adams ◽  
Ifan G. Hughes
Keyword(s):  
Longitudinal Component ◽  
Transverse Component ◽  
Light Fields

This chapter considers how all light fields contain non-transverse components. Situations where it is possible to make the longitudinal component larger than the transverse component are highlighted.

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