Role of nonthermal electron on the dynamics of relativistic electromagnetic soliton in the interaction of laser-plasma (original) (raw)
Related papers
Nondrifting relativistic electromagnetic solitons in plasmas
Laser and Particle Beams, 2003
Low-frequency, relativistic, subcycle solitary waves are found in two-dimensional and three-dimensional particle-in-cell~PIC! numerical simulations, as a result of the interaction of ultrashort, high-intensity laser pulses with plasmas. Moreover, nondrifting, subcycle relativistic electromagnetic solitons have been obtained as solutions of the hydrodynamic equations for an electron-ion warm plasma, by assuming the quasi-neutrality character of the plasma response. In addition, the formation of long-living macroscopic soliton-like structures has been experimentally observed by means of the proton imaging diagnostics. Several common features result from these investigations, as, for example, the quasi-neutral plasma response to the soliton radiation, in the long-term evolution of the system, which leads to the almost complete expulsion of the plasma from the region where the electromagnetic radiation is concentrated, even at subrelativistic field intensity. The results of the theoretical investigations are reviewed with special attention to these similarities.
Physics of Plasmas, 2011
The experimental evidence of the correlation between the initial electron density of the plasma and electromagnetic soliton excitation at the wake of an intense (10 19 W=cm 2 ) and short (1 ps) laser pulse is presented. The spatial distribution of the solitons, together with their late time evolution into post-solitons, is found to be dependent upon the background plasma parameters, in agreement with published analytical and numerical findings. The measured temporal evolution and electrostatic field distribution of the structures are consistent with their late time evolution and the occurrence of multiple merging of neighboring post-solitons.
A kinetic model for the one-dimensional electromagnetic solitons in an isothermal plasma
Physics of Plasmas, 2002
Two nonlinear second order differential equations for the amplitude of the vector potential and for the electromagnetic potential are derived, starting from the full Maxwell equations where the field sources are calculated by integrating in the momentum space the particle distribution function, which is an exact solution of the relativistic Vlasov equation. The resulting equations are exact in describing a hot one-dimensional plasma sustaining a relativistically intense, circularly polarized electromagnetic polarized electromagnetic radiation. The case of standing soliton-like structures in an electron-positron plasma is then investigated. It is demonstrated that at ultrarelativistic temperatures extremely large amplitude solitons can be formed in a strongly overdense plasma.
Electromagnetic solitons in degenerate relativistic electron–positron plasma
Physica Scripta, 2015
The existence of soliton-like electromagnetic (EM) distributions in a fully degenerate electronpositron plasma is studied applying relativistic hydrodynamic and Maxwell equations. For circularly polarized wave it is found that the soliton solutions exist both in relativistic as well as nonrelativistic degenerate plasmas. Plasma density in the region of soliton pulse localization is reduced considerably. The possibility of plasma cavitation is also shown.
Stimulated Raman scattering and Cascade-into-Condensate mechanism induced by intense laser in underdense uniform plasmas are studied by particle simulations. Standing-, backward- and forward-accelerated relativistic electromagnetic (EM) solitons are observed after multiple interactions. Apart from the inhomogeneity of plasma density the soliton acceleration depends upon both the laser intensity and the plasma length. The backward and forward solitons are accelerated towards the plasma-vacuum interface radiating energy in the form of low-frequency EM bursts. The soliton frequency is about one-half of the unperturbed electron plasma frequency. The transverse electric, magnetic and electrostatic fields have half-, one- and one-cycle structure in space, respectively.
Applied Physics B, 2008
The generation of relativistic electromagnetic solitons in plasma with spatiotemporal density modulation is investigated. When two counter-propagating laser pulses overlap in underdense plasma, the interaction between the pulses and plasma modulates the electron and ion densities resulting in localized, stable, long-living relativistic electromagnetic solitons. They are caused by the Stimulated Raman Scattering instability. The dependence of the formation of relativistic electromagnetic solitons on the ion motion, plasma parameters, and laser parameters is studied by particle-in-cell simulations as well.
On the Formation of Solitons in an Isothermal Relativistic Plasma with Positive and Negative Ions
1994
We have studied the phenomenon of solitary wave formation in a relativistic plasma having both positive and negative ions. The state of the plasma is assumed to be isothermal and ions are considered to be warm. The phase velocity, width and amplitude of the soliton are explicitly obtained as functions of σα, σβ , nβ0/nα0, uα0/c, uβ0/c and Q, where σα and σβ are the temperatures of the two kinds of ions, nα0 and nβ0 are the respective equilibrium densities, uα0 and uβ0 are the corresponding streaming velocities and Q is the mass ratio of the negative and positive ions.
Study of electromagnetic solitons excited by different profile pulses
Journal of Theoretical and Applied Physics, 2018
In the present paper, we see the effect of shapes of perturbing pulses on the evolution of electromagnetic solitons in a plasma having nonrelativistic ions and electrons. For this, we make use of IMEX scheme in our simulations, which is an invariant scheme for the two-fluid plasma flow equations. In particular, the impact of ion-to-electron mass ratio, electronto-ion temperature ratio and the width of perturbing pulse is examined on the phase velocity, peak amplitude and width of the solitons.
Head-on Collisions of Electrostatic Solitons in Nonthermal Plasmas
2012
In contrast to overtaking interactions, head-on collisions between two electrostatic solitons can only be dealt with by an approximate method, which limits the range of validity but offers valuable insights. Treatments in the plasma physics literature all use assumptions in the stretching of space and time and in the expansion of the dependent variables that are seldom if ever discussed. All models force a separability to lowest order, corresponding to two linear waves with opposite but equally large velocities. A systematic exposition of the underlying hypotheses is illustrated by considering a plasma composed of cold ions and nonthermal electrons. This is general enough to yield critical compositions that lead to modified rather than standard Korteweg-de Vries equations, an aspect not discussed so far. The nonlinear evolution equations for both solitons and their phase shifts due to the collision are established. A Korteweg-de Vries description is the generic conclusion, except when the plasma composition is critical, rendering the nonlinearity in the evolution equations cubic, with concomitant repercussions on the phase shifts. In the latter case, the solitons can have either polarity, so that combinations of negative and positive solitons can occur, contrary to the generic case, where both solitons necessarily have the same polarity.
Solitons in Relativistic Plasmas by He’s Variational Principle
Applied Physics Research, 2010
The dynamics of electromagnetic solitons in relativistic plasmas is studied in this paper by the aid of He's semi-inverse variational principle. Both Kerr law as well as power law nonlinearity are studied in this paper. The domain restriction of the soliton parameters and the perturbation coefficients are identified.