Anomalous Radiation from a Nonstationary Plasma

Abstract

This paper considers the anomalous growth of the radiation intensity, which is caused by an EM wave incident on an inhomogeneous nonstationary plasma. The amplitude of the reflected signal can thus during relatively short time intervals be larger than that of the incident wave. The reason is that the plasma parameters can pass through values, for which linear resonance of leaking surface waves exist. An analytical expression is obtained for the maximum value of the intensity of the reflected wave for two different plasma density profiles, interacting with waves of different polarization. It is shown that the effect can occur repeatedly in a nonstationary plasma with a nonmonotonous density profile, if the region, where the inhomogeneity gradient changes sign, increases.* Below we consider only the case where the planes defined by the vectors k , , E and k, , 6 , ( 6 , is the unit vector along the z-axis) are identical.

Laser excitation of surface plasma waves over a diffuse plasma boundary

“…The laser can also couple to SPWs in the presence of surface nonuniformity. This work can be extended to the study of SPW excitation through a nonstationary diffuse plasma [18] and diffuse metamaterials [19].…”

“…Lee and Cho [17] studied the excitation of SPWs by parametric decay of a light wave on a plasma-vacuum interface. Gradov et al [18] studied the growth of radiation intensity of an electromagnetic wave incident on an inhomogeneous, nonstationary plasma. Excitation of surface waves in layered structures and metamaterials was studied by Brodin et al [19].…”

Reflection of an electromagnetic pulse incident on a magnetoactive nonlinear medium

“…However, in this article, we consider the displacement vector D to be in the form φ [F, G],where F and G are functions of E and B, and using this method we generalize the work of [2] to calculate the reflection coefficient R, and show that it is a function of time [4]. Other notable results of this work are as follows: (e) There is radiation from the nonlinear medium in the presence of an external magnetic field; this behavior also occurs in nonstationary plasmas [4][5][6].…”

Exciting of Strong Electrostatic Fields and Electromagnetic Resonators at the Plasma Boundary by a Power Electromagnetic Beam

“…The dynamics of the development of the cavity were represented as follows. First, a small space formednear the surface of the plasma and close to the center of the beam with a boundary separating the bulk of the electrons and having a surface shape similar to function (6). As it moveddeeper into the plasma, this cavity wasformed in accordance with the values of the plasma and radiation parameters acting at each time.…”

“…Therefore, identifying such conditions and characterizing interactions in simple modeling cases appearsto be an important primary step toward detecting and predicting many interesting phenomena. It was within the framework of the simplest models of cold plasma with a sharp boundary that the effects of nonlinear transparency [1][2][3], complete absorption [4,5], and anomalous radiation [6] of electromagnetic radiation were investigated. The construction of such a model impliedan accurate representation of the physical essence of the phenomenon under study and those basic features of the interaction of radiation with plasma that ensured its existence.…”