Journal articles: 'Poynting vector and energy'

1

Krumm, Peter, and Donald Bedford. "The gravitational Poynting vector and energy transfer." American Journal of Physics 55, no. 4 (April 1987): 362–63. http://dx.doi.org/10.1119/1.15172.

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Janhunen, P., A. Olsson, N. A. Tsyganenko, C. T. Russell, H. Laakso, and L. G. Blomberg. "Statistics of a parallel Poynting vector in the auroral zone as a function of altitude using Polar EFI and MFE data and Astrid-2 EMMA data." Annales Geophysicae 23, no. 5 (July 28, 2005): 1797–806. http://dx.doi.org/10.5194/angeo-23-1797-2005.

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Abstract. We study the wave-related (AC) and static (DC) parallel Poynting vector (Poynting energy flux) as a function of altitude in auroral field lines using Polar EFI and MFE data. The study is statistical and contains 5 years of data in the altitude range 5000–30000 km. We verify the low altitude part of the results by comparison with earlier Astrid-2 EMMA Poynting vector statistics at 1000 km altitude. The EMMA data are also used to statistically compensate the Polar results for the missing zonal electric field component. We compare the Poynting vector with previous statistical DMSP satellite data concerning the electron precipitation power. We find that the AC Poynting vector (Alfvén-wave related Poynting vector) is statistically not sufficient to power auroral electron precipitation, although it may, for Kp>2, power 25–50% of it. The statistical AC Poynting vector also has a stepwise transition at R=4 RE, so that its amplitude increases with increasing altitude. We suggest that this corresponds to Alfvén waves being in Landau resonance with electrons, so that wave-induced electron acceleration takes place at this altitude range, which was earlier named the Alfvén Resonosphere (ARS). The DC Poynting vector is ~3 times larger than electron precipitation and corresponds mainly to ionospheric Joule heating. In the morning sector (02:00–06:00 MLT) we find that the DC Poynting vector has a nontrivial altitude profile such that it decreases by a factor of ~2 when moving upward from 3 to 4 RE radial distance. In other nightside MLT sectors the altitude profile is more uniform. The morning sector nontrivial altitude profile may be due to divergence of the perpendicular Poynting vector field at R=3–4 RE. Keywords. Magnetospheric physics (Auroral phenomena; Magnetosphere-ionosphere interactions) – Space plasma physics (Wave-particle interactions)

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Ĉakareski, ??, and A. E. Emanuel. "Poynting vector and the quality of electric energy." European Transactions on Electrical Power 11, no. 6 (November 2001): 375–81. http://dx.doi.org/10.1002/etep.4450110605.

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Pelosi, Giuseppe, and Stefano Selleri. "Energy in Electromagnetism: The Poynting Vector [Historical Corner]." IEEE Antennas and Propagation Magazine 59, no. 6 (December 2017): 148–53. http://dx.doi.org/10.1109/map.2017.2752641.

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Morris, Noah A., and Daniel F. Styer. "Visualizing Poynting vector energy flow in electric circuits." American Journal of Physics 80, no. 6 (June 2012): 552–54. http://dx.doi.org/10.1119/1.3679838.

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Ustinov, Andrey, Svetlana Khonina, and Alexey Porfirev. "Formation of Inverse Energy Flux in the Case of Diffraction of Linearly Polarized Radiation by Conventional and Generalized Spiral Phase Plates." Photonics 8, no. 7 (July 16, 2021): 283. http://dx.doi.org/10.3390/photonics8070283.

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Recently, there has been increased interest in the shaping of light fields with an inverse energy flux to guide optically trapped nano- and microparticles towards a radiation source. To generate inverse energy flux, non-uniformly polarized laser beams, especially higher-order cylindrical vector beams, are widely used. Here, we demonstrate the use of conventional and so-called generalized spiral phase plates for the formation of light fields with an inverse energy flux when they are illuminated with linearly polarized radiation. We present an analytical and numerical study of the longitudinal and transverse components of the Poynting vector. The conditions for maximizing the negative value of the real part of the longitudinal component of the Poynting vector are obtained.

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Stafeev, S. S., and V. V. Kotlyar. "Formation of an elongated region of energy backflow using ring apertures." Computer Optics 43, no. 2 (April 2019): 193–99. http://dx.doi.org/10.18287/2412-6179-2019-43-2-193-199.

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In this paper, we have investigated the focusing of a second-order cylindrical vector beam by using a high numerical aperture (NA) lens limited by a ring aperture using the Richards-Wolf formulae. It was shown that the range of negative on-axis projections of the Poynting vector could be increased by increasing the depth of focus through the use of a ring aperture. It was shown that when focusing light with a lens with NA = 0.95, the use of a ring aperture limiting the entrance pupil angle to 0.9 of maximum, allows the depth of the region of negative on-axis Poynting vector projections to be four times increased, with the region width remaining almost unchanged and varying from 0.357 to 0.352 of the incident wavelength. Notably, the magnitude of the reverse energy flow was found to be larger than the direct one by a factor of 2.5.

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Gadre, Nitin Ramchandra. "A relook at radiation by a point charge. I." Canadian Journal of Physics 95, no. 11 (November 2017): 1142–49. http://dx.doi.org/10.1139/cjp-2017-0071.

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Efforts to suggest a classical model for the hydrogen atom are discouraged by a conclusion, based on the principles of electrodynamics, that an accelerating charged particle necessarily radiates. In this paper, we re-examine the steps leading to this conclusion. We start with the relativistic expressions for energy and momentum of a particle and establish the relationship between special relativity and electrodynamics. The standard field expression and its relativistic transformations are then studied for a point charge source, represented by a delta function. In conventional Poynting’s theorem analysis, the rate of change of work done on a system of charges is written as addition of two terms, rate of change of stored energy, and surface integral of Poynting vector. For a delta function source, the first two terms of this equation are either non-integrable or difficult to evaluate. Only the third surface integration term can be evaluated, which is said to give radiation by the point charge. Thus, the statement that an accelerated charge radiates is a conclusion based on this Poynting vector analysis. We examine it and realize that this statement, namely, that a point charge radiates continuously just because it is accelerating, does not have adequate theoretical justification.

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Herrmann, F., and G. Bruno Schmid. "The Poynting vector field and the energy flow within a transformer." American Journal of Physics 54, no. 6 (June 1986): 528–31. http://dx.doi.org/10.1119/1.14554.

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Faria, J. A. B. "Poynting Vector Flow Analysis for Contactless Energy Transfer in Magnetic Systems." IEEE Transactions on Power Electronics 27, no. 10 (October 2012): 4292–300. http://dx.doi.org/10.1109/tpel.2012.2191421.

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BINI, DONATO, ROBERT T. JANTZEN, and GIOVANNI MINIUTTI. "ELECTROMAGNETIC-LIKE BOOST TRANSFORMATIONS OF WEYL AND MINIMAL SUPER-ENERGY OBSERVERS IN BLACK HOLE SPACETIMES." International Journal of Modern Physics D 11, no. 09 (October 2002): 1439–50. http://dx.doi.org/10.1142/s0218271802002414.

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The transformation laws for the electric and magnetic parts of the electromagnetic 2-form and the Weyl tensor under a boost are studied using the complex vector approach, which shows the close analogy between the two cases. For a nonnull electromagnetic field, one can always find an observer who sees parallel electric and magnetic fields (vanishing Poynting vector) and also sees a minimum electromagnetic energy density (and minimum electric and magnetic field magnitudes) compared to other observers. For Weyl fields of all Petrov types except III, and boosts along certain directions of the Weyl principal tetrad, the more complicated Weyl transformation closely mimics the electromagnetic boost transformation, allowing one to extend the electromagnetic results directly to the families of boosts along those directions. In particular for black hole spacetimes, the alignment of the electric and magnetic parts of the Weyl tensor (vanishing super-Poynting vector) leads to minimal gravitational super-energy as seen by the Carter observer within the family of all circularly rotating observers at each spacetime point outside the horizon.

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Yan, Jia, and Thomas A. Dickens. "Reverse time migration angle gathers using Poynting vectors." GEOPHYSICS 81, no. 6 (November 2016): S511—S522. http://dx.doi.org/10.1190/geo2015-0703.1.

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Angle-domain common-image gathers provide much useful data about the subsurface, such as seismic velocities and amplitude-versus-angle (AVA) information, and they can be manipulated to provide high-quality stacked images. However, the computation of angle gathers for reverse time migration (RTM), the most physically accurate migration algorithm, has proven to be costly in terms of computer time and memory usage. We have developed an algorithm for computing RTM angle gathers in a relatively efficient manner. Our method is based on the construction of the directions of propagation of the source and receiver wavefields, given by the direction of energy flux, known as the Poynting vector. The computation is carried out in the space-time domain, avoiding the need to transform the wavefield to, for example, frequency-wavenumber space, as is needed for methods based on wavefront projection. Given accurate Poynting vectors for source and receiver wavefields, one may compute the local reflection angle and azimuth, as well as the reflector dip and azimuth. An important advantage of our method is that it is based on local direction information at the reflection point, and thus it avoids the loss of resolution and smearing that can occur with some other techniques. A simple implementation of the Poynting-vector method can lead to noisy gathers, with leakage between angle bins, caused by unstable division of the local wavefields. We have developed an efficient technique to mitigate this noise and evaluated examples illustrating the aforementioned smearing issues of the subsurface-offset-based gathers and the improvements in the Poynting-vector gathers arising from our algorithm enhancement. Finally, the use of angle gathers for AVA analysis requires that (relative) amplitudes as a function of angle be correct. To this end, we derive weight functions for computing gathers with the correct AVA behavior. We determine the correctness of these weights by testing them with synthetic data.

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Giardino, Sergio. "Quaternionic electrodynamics." Modern Physics Letters A 35, no. 39 (November 2, 2020): 2050327. http://dx.doi.org/10.1142/s0217732320503277.

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We develop a quaternionic electrodynamics and show that it naturally supports the existence of magnetic monopoles. We obtained the field equations, the continuity equation, the electrodynamic force law, the Poynting vector, the energy conservation, and the stress-energy tensor. The formalism also enabled us to generalize the Dirac monopole and the charge quantization rule.

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Franek, Jaroslav. "On Induction Heating - Conductor Excited by External Field." Journal of Electrical Engineering 64, no. 4 (June 1, 2013): 261–64. http://dx.doi.org/10.2478/jee-2013-0038.

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Electromagnetic field in a banded strip conductor excited by external AC voltage driven coil is analyzed. Inhomogeneous wave equation describing this axis-symmetrical configuration is deduced and solved to find the induced current density and the directional energy flux density (Poynting vector) in the conductor.

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Yan, Zhe, Yonglong Yang, and Shaoyong Liu. "True Amplitude Angle Gathers from Reverse Time Migration by Wavefield Decomposition at Excitation Amplitude Time." Energies 13, no. 23 (November 25, 2020): 6204. http://dx.doi.org/10.3390/en13236204.

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Reservoir parameter estimation is one of the goals of amplitude-versus-angle (AVA) inversion and angle-domain common image gathers are the basis of AVA inversion. Therefore, the accuracy of kinematic and kinetic information on angle gathers is very important for reservoir characterization. Reverse time migration is one of the most physically accurate migration method. Generating angle gathers from reverse time migration with the Poynting vector method is very efficient. However, due to inaccurate angle measurement and uneven illumination, angle gathers calculated by the Poynting vector method are often not suitable for AVA inversion. In this paper, we propose an efficient method of angle gathers with accurate angular information and amplitude from reverse time migration. We firstly decompose source and receiver wavefield to their up-going and down-going parts by using analytic wavefield. We calculate propagation directions for source down-going wavefield and receiver up-going wavefield by the Poynting vector method and form the angle gathers with these angle information and decomposed wavefield. To reduce memory storage and improve computational efficiency, we decompose wavefield at excitation amplitude time by using a local spatial Fourier transform. We also use a spatial smoothed Poynting vector to improve the stability of angle measurement. We apply an illumination compensation image condition to recover the true amplitude. Numerical examples on Marmousi model and the SEAM two-dimensional (2D) model demonstrate the advantages of our proposed method. The angle gathers based on our method are cleaner with more focus on events energy and better continuity, suffering from less low-frequency noise in the shallow parts and with a distinct cutoff at large angle where reflection terminates. At last, we demonstrate the effectiveness of proposed method on a 2D marine field data example.

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Nazarov, S. A. "The Mandelstam Energy Radiation Conditions and the Umov–Poynting Vector in Elastic Waveguides." Journal of Mathematical Sciences 195, no. 5 (November 9, 2013): 676–729. http://dx.doi.org/10.1007/s10958-013-1612-2.

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Fedosin, Sergey G. "Equations of Motion in the Theory of Relativistic Vector Fields." International Letters of Chemistry, Physics and Astronomy 83 (August 2019): 12–30. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.83.12.

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Within the framework of the theory of relativistic vector fields, the covariant expressions are presented for the equations of motion of the matter and the field. These expressions can be written either in terms of the field tensors, that is, the fields’ strengths and solenoidal vectors, or in terms the four-potentials, that is, the fields’ scalar and vector potentials. This state of things is due to the fact that the Lagrange function initially implied the complementarity of description in terms of the strengths and the field potentials. It is shown that the equation for the fields, obtained by taking the covariant derivative in the equation for the metric, has a deeper meaning than the ordinary equation of motion of the matter, found with the help of the principle of least action. In particular, the above-mentioned equation for the fields leads to the generalized Poynting theorem, and after integration over the volume it allows us to introduce for consideration the integral vector as a measure of the energy and the fields’ energy fluxes, associated with a system of particles and fields.

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Todeschini, Grazia, Alexander E. Emanuel, Alessandro Ferrero, and Adriano Paolo Morando. "A Poynting Vector Approach to the Study of the Steinmetz Compensator." IEEE Transactions on Power Delivery 22, no. 3 (July 2007): 1830–33. http://dx.doi.org/10.1109/tpwrd.2007.899766.

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Schlickeiser, R. "Poynting vector, energy densities, and pressure of collective transverse electromagnetic fluctuations in unmagnetized plasmas." Physics of Plasmas 19, no. 1 (January 2012): 012101. http://dx.doi.org/10.1063/1.3671965.

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20

Schliewe, Jörn. "Electrodynamics in Euclidean Space Time Geometries." Open Physics 17, no. 1 (December 30, 2019): 731–42. http://dx.doi.org/10.1515/phys-2019-0077.

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Abstract In this article it is proven that Maxwell’s field equations are invariant for a real orthogonal Cartesian space time coordinate transformation if polarization and magnetization are assumed to be possible in empty space. Furthermore, it is shown that this approach allows wave propagation with finite field energy transport. To consider the presence of polarization and magnetization an alternative Poynting vector has been defined for which the divergence gives the correct change in field energy density.

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Kozlova, E. S., S. S. Stafeev, S. A. Fomchenkov, V. V. Podlipnov, and V. V. Kotlyar. "Transverse intensity at the tight focus of a second-order cylindrical vector beam." Computer Optics 45, no. 2 (April 2021): 165–71. http://dx.doi.org/10.18287/2412-6179-co-835.

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In this paper, an effect of a reverse energy flow at the focus of a second-order cylindrical vector beam which passed through amplitude zone plate was investigated with a scanning near-field optical microscope. A comparison of the intensity distribution detected with a pyramidal metallized cantilever with a hole and the characteristics of the light field calculated using a FDTD method and the Richards-Wolf formulas suggests that the cantilever is sensitive to the transverse intensity component rather than the total intensity or the components of the Poynting vector in the backflow region.

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Nalimov, A. G. "Energy flux of a vortex field focused using a secant gradient lens." Computer Optics 44, no. 5 (October 2020): 707–11. http://dx.doi.org/10.18287/2412-6179-co-688.

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In this paper we simulated the focusing of left circular polarized beam with a second order phase vortex and a second-order cylindrical vector beam by a gradient index Mikaelian lens. It was shown numerically, that there is an area with a negative Poynting vector projection on Z axis, that can be called an area with backward energy flow. Using a cylindrical hole in the output surface of the lens and optimizing it one can obtain a negative flow, which will be situated in the maximum intensity region, unlike to previous papers, in which such backward energy flow regions were situated in a shadow area. Thereby, this lens will work as an “optical magnet”, it will attract Rayleigh particles (with diameter about 1/20 of the wavelength) to its surface.

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Nalimov, A. G., and S. S. Stafeev. "Linear to circular polarization conversion in the sharp focus of an optical vortex." Computer Optics 45, no. 1 (February 2021): 13–18. http://dx.doi.org/10.18287/2412-6179-co-778.

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We have shown that when sharply focusing a linearly polarized optical vortex with topological charge 2, in the near-axis region of the focal plane, not only does a reverse energy flow (the negative on-axis projection of the Poynting vector) occur, but also the right-handed circular polariza-tion of light. Moreover, due to spin-orbital angular momentum conversion, the on-axis polarization vector and the transverse energy flow rotate around the optical axis in the same direction (counter-clockwise). If an absorbing spherical microparticle is put in the focus on the optical axis, it will rotate around the axis and around its center of mass counterclockwise. Numerical simulation results confirms the theoretical predictions.

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Stafeev, S. S. "An orbital energy flow and a spin flow at the tight focus." Computer Optics 45, no. 4 (July 2021): 520–24. http://dx.doi.org/10.18287/2412-6179-co-867.

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We have shown that a reverse energy flow (negative projection of the Poynting vector onto the optical axis) at the sharp focus of an optical vortex with topological charge 2 and left-hand circular polarization arises because the axial spin flow has a negative projection onto the optical axis and is greater in magnitude than positive projection onto the optical axis of the orbital energy flow (canonical energy flow). Also, using the Richards-Wolf formulas, it is shown that when focusing a left-handed circularly polarized light, in the region of the on-axis reverse energy flow, the light is right-handed circularly polarized.

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Yang, Jia Jia, Bing Shou He, and Ting Chen. "Angle-Domain Gathers Computation Using Poynting Vector of Two-Way Acoustic Wave Equation." Advanced Materials Research 962-965 (June 2014): 2984–87. http://dx.doi.org/10.4028/www.scientific.net/amr.962-965.2984.

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Based on two-way acoustic wave equation, we present a method for computing angle-domain common-image gathers for reverse time migration. The method calculates the propagation direction of source wave-fields and receiver wave-fields according to expression of energy flow density vectors (Poynting vectors) of acoustic wave equation in space-time domain to obtain the reflection angle, then apply the normalized cross-correlation imaging condition to achieve the angle-domain common-image gathers. The angle gathers obtained can be used for migration velocity analysis, AVA analysis and so on. Numerical examples and real data examples demonstrate the effectiveness of this method.

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AUCI, MASSIMO, and GUIDO DEMATTEIS. "AN APPROACH TO UNIFYING CLASSICAL AND QUANTUM ELECTRODYNAMICS." International Journal of Modern Physics B 13, no. 12 (May 20, 1999): 1525–57. http://dx.doi.org/10.1142/s0217979299001569.

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The foundations of quantum mechanics (QM) can find a consistent and exhaustive explanation in a new theoretical context. The "Approach" allows us to justify both classical and quantum electromagnetic phenomenology by using classical concepts. In this paper we review the bases of the attempt originating form the role that the transverse component of the Poynting vector plays in localising energy in the neighbourhood of an electromagnetic source and we analyse the quantum implications.

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Tabatadze, Vasil, Eldar Veliyev, Ertugrul Karacuha, and Kamil Karacuha. "The Diffraction by the Half-plane with the Fractional Boundary Condition." Applied Computational Electromagnetics Society 35, no. 11 (February 5, 2021): 1386–87. http://dx.doi.org/10.47037/2020.aces.j.351162.

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In this article, there is considered the electromagnetic plane wave diffraction by the half-plane with fractional boundary conditions. As a mathematical tool, the fractional calculus is used. The theoretical part is given based on which the near field, Poynting vector and energy density distribution are calculated. Interesting results are obtained for the fractional order between marginal values, which describes a new type of material with new properties. The results are analyzed.

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Calamaro, N., Y. Beck, and D. Shmilovitz. "A review and insights on Poynting vector theory and periodic averaged electric energy transport theories." Renewable and Sustainable Energy Reviews 42 (February 2015): 1279–89. http://dx.doi.org/10.1016/j.rser.2014.10.065.

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Grabinski, Hartmut, and Fred Wiznerowicz. "Energy transfer on three-phase high-voltage lines: the strange behavior of the Poynting vector." Electrical Engineering 92, no. 6 (September 29, 2010): 203–14. http://dx.doi.org/10.1007/s00202-010-0176-0.

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Stafeev, S. S., and V. D. Zaitsev. "Focusing fractional-order cylindrical vector beams." Computer Optics 45, no. 2 (April 2021): 172–78. http://dx.doi.org/10.18287/2412-6179-co-805.

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By numerically simulating the sharp focusing of fractional-order vector beams (0≤m≤1, with azimuthal polarization at m=1 and linear polarization at m=0), it is shown that the shape of the intensity distribution in the focal spot changes from elliptical (m=0) to round (m=0.5) and ends up being annular (m=1). Meanwhile, the distribution pattern of the longitudinal component of the Poynting vector (energy flux) in the focal spot changes in a different way: from circular (m=0) to elliptical (m=0.5) and ends up being annular (m=1). The size of the focal spot at full width at half maximum of intensity for a first-order azimuthally polarized optical vortex (m=1) and numerical aperture NA=0.95 is found to be 0.46 of the incident wavelength, whereas the diameter of the on-axis energy flux for linearly polarized light (m=0) is 0.45 of the wavelength. Therefore, the answers to the questions: when the focal spot is round and when elliptical, or when the focal spot is minimal -- when focusing an azimuthally polarized vortex beam or a linearly polarized non-vortex beam, depend on whether we are considering the intensity at the focus or the energy flow. In another run of numerical simulation, we investigate the effect of the deviation of the beam order from m=2 (when an energy backflow is observed at the focal spot center). The reverse energy flow is shown to occur at the focal spot center until the beam order gets equal to m=1.55.

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MA, ZHONG-SHUI. "ADIABATIC ROTATION FOR THE SKYRMIONS." Modern Physics Letters A 08, no. 37 (December 7, 1993): 3569–73. http://dx.doi.org/10.1142/s0217732393002300.

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We study the electromagnetic properties of the skyrmions of the O(3) nonlinear sigma model in (2+1) dimensions coupled with the Chern-Simons field by the adiabatic rotation procedure. It is shown that there is no Poynting vector for the skyrmion configuration and the Chern-Simons gauge field. In the process, an explicit derivation of the angular momentum is presented, which connects with the fractional statistics for the skyrmions.

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Sharif, M., and Rubab Manzoor. "Dark energy and collapsing axial system." International Journal of Modern Physics D 26, no. 06 (December 2016): 1750057. http://dx.doi.org/10.1142/s0218271817500572.

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This paper investigates the effects of dark source term on the dissipative axially symmetric collapse by taking self-interacting Brans–Dicke (SBD) gravity as a dark energy (DE) candidate. We discuss physically feasible energy source of the model and formulate all the dynamical variables as well as structure scalars. It is found that the dark source term is one of the source of anisotropy and dissipation in the system. Further, we obtain structure scalars in this background. In order to discuss factors describing dissipative collapse, we develop equations related to the evolution of dynamical variables, heat transport equation as well as super-Poynting vector. We conclude that the thermodynamics of the collapse, evolution of kinematical terms (like expansion scalar, shear and vorticity) and inhomogeneity are affected by dark source term. Finally, we study the existence of radiation having repulsive gravitational nature in this collapse scenario.

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Kotlyar, V. V., S. S. Stafeev, and A. G. Nalimov. "Vortex energy flow in the tight focus of a non-vortex field with circular polarization." Computer Optics 44, no. 1 (February 2020): 5–11. http://dx.doi.org/10.18287/2412-6179-co-582.

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Using Richards-Wolf formulas, we show that an axisymmetric circularly polarized vortex-free field can be focused into a sharp subwavelength focal spot, around which there is a region where the light energy flow propagates along a spiral. This effect can be explained by the conversion of the spin angular momentum of the circularly polarized field into the orbital angular momentum near the focus, although the on-axis orbital angular momentum remains zero. It is also shown that a linearly polarized optical vortex with topological charge 2 forms near the focal plane an on-axis reverse energy flow (defined by the negative longitudinal component of the Poynting vector) whose amplitude is comparable with the direct energy flow.

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Vargas-Rodríguez, H., A. Gallegos, M. A. Muñiz-Torres, H. C. Rosu, and P. J. Domínguez. "Relativistic Rotating Electromagnetic Fields." Advances in High Energy Physics 2020 (December 29, 2020): 1–17. http://dx.doi.org/10.1155/2020/9084046.

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In this work, we consider axially symmetric stationary electromagnetic fields in the framework of special relativity. These fields have an angular momentum density in the reference frame at rest with respect to the axis of symmetry; their Poynting vector form closed integral lines around the symmetry axis. In order to describe the state of motion of the electromagnetic field, two sets of observers are introduced: the inertial set, whose members are at rest with the symmetry axis; and the noninertial set, whose members are rotating around the symmetry axis. The rotating observers measure no Poynting vector, and they are considered as comoving with the electromagnetic field. Using explicit calculations in the covariant 3 + 1 splitting formalism, the velocity field of the rotating observers is determined and interpreted as that of the electromagnetic field. The considerations of the rotating observers split in two cases, for pure fields and impure fields, respectively. Moreover, in each case, each family of rotating observers splits in two subcases, due to regions where the electromagnetic field rotates with the speed of light. These regions are generalizations of the light cylinders found around magnetized neutron stars. In both cases, we give the explicit expressions for the corresponding velocity fields. Several examples of relevance in astrophysics and cosmology are presented, such as the rotating point magnetic dipoles and a superposition of a Coulomb electric field with the field of a point magnetic dipole.

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Vinogradov, S. S., and A. V. Sulima. "Calculation of the poynting vector flux through a partially screened dielectric sphere." Radiophysics and Quantum Electronics 32, no. 2 (February 1989): 160–66. http://dx.doi.org/10.1007/bf01039672.

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Zdagkas, Apostolos, Nikitas Papasimakis, Vassili Savinov, Mark R. Dennis, and Nikolay I. Zheludev. "Singularities in the flying electromagnetic doughnuts." Nanophotonics 8, no. 8 (June 22, 2019): 1379–85. http://dx.doi.org/10.1515/nanoph-2019-0101.

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AbstractFlying doughnuts (FDs) are exact propagating solutions of Maxwell equations in the form of single-cycle, space-time non-separable toroidal pulses. Here we review their properties and reveal the existence of a complex and robust fine topological structure. In particular, the electric and magnetic fields of the FD pulse vanish across a number of planes, spherical shells and rings, and display a number of point singularities including saddle points and vortices. Moreover, the instantaneous Poynting vector of the field exhibits a large number of singularities, which are often accompanied by extended areas energy backflow.

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CHANYAL, B. C., P. S. BISHT, and O. P. S. NEGI. "OCTONION AND CONSERVATION LAWS FOR DYONS." International Journal of Modern Physics A 28, no. 26 (October 20, 2013): 1350125. http://dx.doi.org/10.1142/s0217751x1350125x.

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Starting with the usual definitions of octonions and split octonions in terms of Zorn vector matrix realization, we have made an attempt to write the continuity equation and other wave equations of dyons in split octonions. Accordingly, we have investigated the work energy theorem or "Poynting Theorem," Maxwell stress tensor and Lorentz invariant for generalized fields of dyons in split octonion electrodynamics. Our theory of dyons in split octonion formulations is discussed in term of simple and compact notations. This theory reproduces the dynamic of electric (magnetic) in the absence of magnetic (electric) charges.

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38

Villavicencio, M., J. L. Jiménez, and JAE Roa-Neri. "On the Cherenkov radiation from extended charge distributions." Canadian Journal of Physics 77, no. 10 (February 15, 2000): 775–84. http://dx.doi.org/10.1139/p99-060.

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In this work the Cherenkov effect for extended charge distributions is analyzed using two different methods. In the first method, the Poynting vector is employed to determine the energy radiated, whereas in the second one, we apply the idea of generating time-dependent elemental dipoles, induced by a charge distribution moving with constant velocity, inside a material medium. An explicit expression for the Cherenkov radiation generated by some different kinds of spherically symmetric charge, travelling inside a medium, is obtained.PACS Nos.: 03.50.De, 41.20.Bt, 41.60.-m, 41.60.Bq

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39

Laitinen, T. V., T. I. Pulkkinen, M. Palmroth, P. Janhunen, and H. E. J. Koskinen. "The magnetotail reconnection region in a global MHD simulation." Annales Geophysicae 23, no. 12 (December 23, 2005): 3753–64. http://dx.doi.org/10.5194/angeo-23-3753-2005.

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Abstract. This work investigates the nature and the role of magnetic reconnection in a global magnetohydrodynamic simulation of the magnetosphere. We use the Gumics-4 simulation to study reconnection that occurs in the near-Earth region of the current sheet in the magnetotail. We locate the current sheet surface and the magnetic x-line that appears when reconnection starts. We illustrate the difference between quiet and active states of the reconnection region: variations in such quantities as the current sheet thickness, plasma flow velocities, and Poynting vector divergence are strong. A characteristic feature is strong asymmetry caused by non-perpendicular inflows. We determine the reconnection efficiency by the net rate of Poynting flux into the reconnection region. The reconnection efficiency in the simulation is directly proportional to the energy flux into the magnetosphere through the magnetopause: about half of all energy flowing through the magnetosphere is converted from an electromagnetic into a mechanical form in the reconnection region. Thus, the tail reconnection that is central to the magnetospheric circulation is directly driven; the tail does not exhibit a cycle of storage and rapid release of magnetic energy. We find similar behaviour of the tail in both synthetic and real event runs.

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Kotlyar, V. V., S. S. Stafeev, and A. A. Kovalev. "Sharp focusing of a light field with polarization and phase singularities of an arbitrary order." Computer Optics 43, no. 3 (June 2019): 337–46. http://dx.doi.org/10.18287/2412-6179-2019-43-3-337-346.

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Using the Richards-Wolf formalism, we obtain general expressions for all components of the electric and magnetic strength vectors near the sharp focus of an optical vortex with the topological charge m and nth-order azimuthal polarization. From these equations, simple consequences are derived for different values of m and n. If m=n>1, there is a non-zero intensity on the optical axis, like the one observed when focusing a vortex-free circularly polarized light field. If n=m+2, there is a reverse flux of light energy near the optical axis in the focal plane. The derived expressions can be used both for simulating the sharp focusing of optical fields with the double singularity (phase and polarization) and for a theoretical analysis of focal distributions of the intensity and the Poynting vector, allowing one to reveal the presence of rotational symmetry or the on-axis reverse energy flux, as well as the focal spot shape (a circle or a doughnut).

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41

Chubykalo, A., A. Espinoza, and R. Tzonchev. "Experimental test of the compatibility of the definitions of the electromagnetic energy density and the Poynting vector." European Physical Journal D 31, no. 1 (October 2004): 113–20. http://dx.doi.org/10.1140/epjd/e2004-00135-x.

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42

Wang, Changbiao. "Self-consistent theory for a plane wave in a moving medium and light-momentum criterion." Canadian Journal of Physics 93, no. 12 (December 2015): 1510–22. http://dx.doi.org/10.1139/cjp-2015-0167.

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A self-consistent theory is developed based on the principle of relativity for a plane wave in a moving non-dispersive, lossless, non-conducting, isotropic, uniform medium. A light-momentum criterion is set up for the first time, which states that the momentum of light in a medium is parallel to the wave vector in all inertial frames of reference. By rigorous analysis, novel basic properties of the plane wave are exposed: (i) Poynting vector does not necessarily represent the electromagnetic (EM) power flow when a medium moves; (ii) Minkowski light momentum and energy constitute a Lorentz four-vector in a form of single EM-field cell or single photon, and Planck constant is a Lorentz invariant; (iii) there is no momentum transfer taking place between the plane wave and the uniform medium, and the EM momentum conservation equation cannot be uniquely determined without resorting to the principle of relativity; and (iv) when the medium moves opposite to the wave vector at a faster-than-dielectric light speed, negative frequency and negative EM energy density occur, with the plane wave becoming left-handed. Finally, a new physics of so-called “intrinsic Lorentz violation” is presented as well.

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43

IVANOV, S. T., N. I. NIKOLAEV, S. NONAKA, and P. N. MALINOV. "The spectrum of electromagnetic waves in a magnetized gaseous plasma layer. Part 2. Anisotropic modes." Journal of Plasma Physics 65, no. 4 (May 2001): 291–303. http://dx.doi.org/10.1017/s0022377801001052.

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A numerical investigation of anisotropic waves propagating in a magnetized plasma layer is performed. In gyrotropic plasma layers, there are two regions in which electromagnetic waves exist owing to the anisotropic properties of the plasma. Mainly these are Rayleigh pseudosurface waves. In the upper anisotropic region, a wave exists only in a planar waveguide. In the lower anisotropic region, there are two waves. The dispersion and the origin of these waves are analysed. The distribution of the energy and the Poynting vector are unique, and they differ from those of other families of electromagnetic waves. At small wavenumbers, the energy is concentrated in one of the dielectrics and at large wavenumbers, it is concentrated in the plasma.

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44

Torricelli-Ciamponi, G. "Energy variations at the onset of the tearing instability." Journal of Plasma Physics 36, no. 2 (October 1986): 251–67. http://dx.doi.org/10.1017/s0022377800011739.

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The resistive instability of a simple one-dimensional current sheet model has been investigated both in the long and in the short wavelength approximation. For the linear phase of the instability it is possible to derive, by means of an expansion technique, an analytical expression for the growth rate and for the perturbation itself. The variations of each kind of energy (magnetic, kinetic and dissipated energies, Poynting vector, work against pressure gradients and magnetic forces) are then exactly computed. Different behaviour of the System is obtained for different wavelengths. In particular, the driving energy for the instability is found to come from different regions: for high wavenumber α there is a decrease of the magnetic energy in the inner resistive region where the reconnection occurs, whereas for low-α modes the magnetic energy decreases in the outer ideal region. Moreover, the amount of Joule dissipation is found to increase with decreasing α so that the low-α regime is the most efficient.

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Ferrero, A., S. Leva, and A. P. Morando. "An approach to the non-active power concept in terms of the poynting-park vector." European Transactions on Electrical Power 11, no. 5 (September 2001): 291–99. http://dx.doi.org/10.1002/etep.4450110503.

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Zou, Lixiang Jackie, Yuan Liu, Yu-Gang Su, and Aiguo Patrick Hu. "Study of power flow mechanism of capacitive power transfer system based on Poynting vector analysis." International Journal of Electrical Power & Energy Systems 134 (January 2022): 107374. http://dx.doi.org/10.1016/j.ijepes.2021.107374.

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47

Power, E. A., and T. Thirunamachandran. "Quantum electrodynamics with nonrelativistic sources. IV. Poynting vector, energy densities, and other quadratic operators of the electromagnetic field." Physical Review A 45, no. 1 (January 1, 1992): 54–63. http://dx.doi.org/10.1103/physreva.45.54.

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Kotlyar, V. V., and S. S. Stafeev. "A transverse energy flow at the tight focus of light with higher-order circular-azimuthal polarization." Computer Optics 45, no. 3 (June 2021): 311–18. http://dx.doi.org/10.18287/2412-6179-co-839.

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Tight focusing of light with mth-order circular-azimuthal polarization was investigated. This is a new type of inhomogeneous hybrid polarization that combines the properties of mth order cylindrical polarization and circular polarization. Using the Richards-Wolf formalism, we obtained analytical expressions in the focal spot for the projections of the electric and magnetic field, the intensity distribution, the projections of the Poynting vector, and the spin angular momentum. It was shown theoretically and numerically that at the focus, the intensity has 2(m+1) local maxima located on a circle centered on an on-axis intensity null. It was shown that 4m vortices of a transverse energy flow were produced at the focus, with their centers located between the local intensity maxima. It was also shown that in the focal plane, the transverse energy flow changes the direction of rotation 2(2m+1) times around the optical axis. It is interesting that the longitudinal projection of the spin angular momentum at the focus changes sign 4m times. In those areas of the focal plane where the transverse energy flow rotates counterclockwise, the longitudinal projection of the spin angular momentum is positive, and the polarization vector rotates counterclockwise in the focal plane. Conversely, if the energy flow rotates clockwise, the polarization vector rotates clockwise, and the longitudinal projection of the spin angular momentum is negative. Numerical simulations are in agreement with the theoretical investigation.

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Czarnecki, L. S. "Closure on "Could Power Properties of Three-Phase Systems Be Described in Terms of Poynting Vector?"." IEEE Transactions on Power Delivery 22, no. 2 (April 2007): 1269–70. http://dx.doi.org/10.1109/tpwrd.2007.893944.

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Czarnecki, L. S. "Discussion of “Could Power Properties of Three-Phase Systems be Described in Terms of Poynting Vector?”." IEEE Transactions on Power Delivery 22, no. 2 (April 2007): 1267–69. http://dx.doi.org/10.1109/tpwrd.2007.893947.

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Journal articles on the topic 'Poynting vector and energy'

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