نتایج جستجو برای: electromagnetic waves
تعداد نتایج: 181493 فیلتر نتایج به سال:
We investigate transverse electromagnetic waves propagating in a plasma influenced by the gravitational field of the Schwarzschild-de Sitter black hole. Applying 3+1 spacetime split we derive the relativistic two-fluid equations to take account of gravitational effects due to the event horizon and describe the set of simultaneous linear equations for the perturbations. We use a local approximat...
Electromagnetic waves are known to exert optical forces on particles through radiation pressure. It was hypothesized previously that electromagnetic waves inside left-handed metamaterials produce negative radiation pressure. Here we numerically examine optical forces inside left-handed photonic crystals demonstrating negative refraction and reversed phase propagation. We demonstrate that even t...
A large family of noncommutative Einstein-Maxwell null pp -waves to order one in the noncommutativity parameters is constructed. They are solutions to the Einstein and field equations for general relativity coupled to a Seiberg-Witten electromagnetic field. Noncommutativity enters the spacetime metric through a conformal factor and is responsible for dilating/contracting the separation between ...
We discuss the propagation of an electromagnetic wavepacket inside a rectangular waveguide, of the type employed in recent experiments on superluminal tunneling of electromagnetic signals. By exploiting the analogy between particle and photon tunneling, we consider both evanescent and growing waves inside the narrowed part of the waveguide. The Fourier expansion of such waves shows that the bar...
Complex electrical activities in cardiac tissue can set up time-varying electromagnetic field. Magnetic flux is introduced into the Fitzhugh-Nagumo model to describe the effect of electromagnetic induction, and then memristor is used to realize the feedback of magnetic flux on the membrane potential in cardiac tissue. It is found that a spiral wave can be triggered and developed by setting spec...
A simple but highly efficient approach for dealing with the problem of cylindrical electromagnetic waves propagation in a nonlinear medium is proposed based on an exact solution proposed recently. We derive an analytical explicit formula, which exhibiting rich interesting nonlinear effects, to describe the propagation of any amount of cylindrical electromagnetic waves in a nonlinear medium. The...
This problem was first discussed by Stokes over 150 years ago [1, 2, 3, 4], who noted that three-dimensional sound waves from a bounded source cannot be unipolar. While his argument applies to electromagnetic waves as well, this is little recognized in the literature. One-dimensional electromagnetic (and sound) waves can be unipolar. A plane wave can have any pulseform, but, strictly speaking, ...
The electromagnetic field solution for a spherical invisibility cloak with an active device inside is established. Extraordinary electric and magnetic surface voltages are induced at the inner boundary of a spherical cloak, which prevent electromagnetic waves from going out. The phase and handness of polarized waves obliquely incident on such boundaries are kept in the reflected waves. The surf...
Here, we report the fabrication of a graphene-based Bragg grating (one-dimensional photonic crystal) and experimentally demonstrate the excitation of surface electromagnetic waves in the periodic structure using prism coupling technique. Surface electromagnetic waves are non-radiative electromagnetic modes that appear on the surface of semi-infinite 1D photonic crystal. In order to fabricate th...
Excitation of upper hybrid waves associated with the ionospheric heating experiments is assumed to be essential in explaining some of the features of stimulated electromagnetic emissions (SEE). A direct conversion process is proposed as an excitation mechanism of the upper hybrid waves where the energy of an obliquely propagating electromagnetic pump wave is converted into the electrostatic upp...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید