Electromagnetic energy penetration in the self-induced transparency regime of relativistic laser-plasma interactions

Two scenarios for the penetration of relativistically intense laser radiation into an overdense plasma, accessible by self-induced transparency, are presented. For supercritical densities less than 1.5 times the critical one, penetration of laser energy occurs by soliton-like structures moving into the plasma. At higher background densities laser light penetrates over a finite length only, that increases with the incident intensity. In this regime plasma-field structures represent alternating electron layers separated by about half a wavelength by depleted regions.Comment: 9 pages, 4 figures, submitted for publication to PR

One-dimensional steady-state structures at relativistic interaction of laser radiation with overdense plasma for finite electron temperature

One-dimensional steady-state plasma-field structures in overdense plasma are studied assuming that the electron temperature is uniform over plasma bulk and the ions are stationary. It is shown that there may exist solutions for electron distributions with cavitation regions in plasma under the action of ponderomotive forceComment: 6 pages, 4 figure

A Study Of Undulator Induced Transparency Of Magnetized Plasma In The Linear Regime

The phenomenon of Undulator Induced Transparency (UIT) in a magnetized plasma is a particular case of the Electromagnetically Induced Transparency (EIT) effect where the absorption of the EM wave at the electron cyclotron frequency in the plasma is eliminated by adding a pump EM field. The UIT effect take place when static helical magnetic undulator is used instead of an EM pump wave, thus enabling the coupling of the transverse and longitudinal DO waves in the plasma. The electromagnetic waves with slow group velocity are generated resulting in an extreme compression of the wave energy in the plasma. The polarization of the hybrid compressed waves are primarily longitudinal and their phase velocity is controllable by the undulator period, making UIT attractive for electron and ion acceleration. Numerical simulations (fluid and PIC) reveal several different scenarios of propagation of the EM waves in the UIT regime depending on the strength of the mode coupling between the two polarizations (right-hand and left-hand).Physic

Optically controlled dense current structures driven by relativistic plasma aperture-induced diffraction

The collective response of charged particles to intense fields is intrinsic to plasma accelerators and radiation sources, relativistic optics and many astrophysical phenomena. Here we show that a \textit{relativistic plasma aperture} is generated in thin foils by intense laser light, resulting in the fundamental optical process of diffraction. The plasma electrons collectively respond to the resulting laser near-field diffraction pattern, producing a beam of energetic electrons with spatial structure which can be controlled by variation of the laser pulse parameters. It is shown that static electron beam, and induced magnetic field, structures can be made to rotate at fixed or variable angular frequencies depending on the degree of ellipticity in the laser polarization. The concept is demonstrated numerically and verified experimentally, and is an important step towards optical control of charged particle dynamics in laser-driven dense plasma sources