Search results for "Classical electromagnetism"
showing 8 items of 8 documents
Modelling chemical composition in electric systems - implications to the dynamics of dye-sensitised solar cells
2010
International audience; Classical electromagnetism provides limited means to model electric generators. To extend the classical theory in this respect, additional information on microscopic processes is required. In semiconductor devices and electrochemical generators such information may be obtained by modelling chemical composition. Here we use this approach for the modelling of dye-sensitised solar cells. We simulate the steady-state current-voltage characteristics of such a cell, as well as its transient response. Dynamic simulations show optoelectronic hysteresis in these cells under transient light pulse illumination.
Synthetic electromagnetic knot in a three-dimensional skyrmion
2018
We experimentally simulate a quantum-mechanical particle interacting with knotted electromagnetic fields.
The electromagnetic field of an accelerated charge in the proper reference frame of a noninertial observer
1989
The Lienard-Wiechert formulae for the electric and magnetic fields of an accelerated charge moving along an arbitrary world-line are generalized so that they can be applied by noninertial observers using accelerating and rotating reference frames. For this purpose, a relativistic coordinate-independent formalism suggested by DeFacio, Dennis and Eetzloff is extended to the description of all kinematical aspects required in the theory of the retarded fields of a point charge. The generalized Lienard-Wiechert formula is applied to a number of special situations, demonstrating that it allows a lucid and concise treatment of a number of subtle problems such as the role of the «relativity of acce…
Energy of dendritic avalanches in thin-film superconductors
2018
A method for calculating stored magnetic energy in a thin superconducting film based on quantitative magneto-optical imaging is developed. Energy and magnetic moment are determined with these calculations for full hysteresis loops in a thin film of the superconductor NbN. Huge losses in energy are observed when dendritic avalanches occur. Magnetic energy, magnetic moment, sheet current and magnetic flux distributions, all extracted from the same calibrated magneto-optical images, are analyzed and discussed. Dissipated energy and the loss in moment when dendritic avalanches occur are related to each other. Calculating these losses for specific spatially-resolved flux avalanches is a great ad…
A perfect Fresnel acoustic reflector implemented by a Fano-resonant metascreen
2018
We propose a perfectly reflecting acoustic metasurface which is designed by replacing the curved segments of the traditional Fresnel reflector by flat Fano-resonant sub-wavelength unit cells. To preserve the original Fresnel focusing mechanism, the unit cell phase follows a specific phase profile which is obtained by applying the generalized Snell's law and Fermat's principle. The reflected curved phase fronts are thus created at the air-metasurface boundary by tailoring the metasurface dispersion as dictated by Huygens' principle. Since the unit cells are implemented by sub-wavelength double slit-shaped cavity resonators, the impinging sound waves are perfectly reflected producing acoustic…
Self-dressing and radiation reaction in classical electrodynamics
2002
A canonical approach to self-dressing in classical electrodynamics is presented. A slowly moving, rigid charge distribution is assumed to be completely deprived of the transverse electric E⊥ at an initial time t1' and the development of this component of the field is studied for t > t1' by solving the coupled charge-field Hamilton equations of motion. The theory is specialized to charge distributions of spherical symmetry, and in particular the point-charge, the spherical shell of charge and the spherical volume of charge are considered. As for the dynamics of the charge, the radiation-reaction force during self-dressing is obtained and it is shown to be substantially different at short tim…
Locality, QED and classical electrodynamics
1998
We report on some conceptual changes in our present understanding of Quantum Field Theory and muse about possible consequences for the understanding of $v>c$ signals.
The Action Principle in Classical Electrodynamics
2001
The main purpose of this chapter is to consider the formulation of a relativistic point particle in classical electrodynamics from the viewpoint of Lagrangian mechanics. Here, the utility of Schwinger’s action principle is illustrated by employing three different kinds of action to derive the equations of motion and the associated surface terms.