Nonlinear Interaction Of Electromagnetic Waves Research Articles

Nonlinear interaction of electromagnetic wave with electron acoustic wave in plasma

An analysis on the nonlinear interaction of electromagnetic waves with electron acoustic waves is performed in plasma with two different temperature electron fluids in the presence of a neutralizing static ion background. A newly structured Zakharov’s equations are derived employing two fluid two-time scale theory. These coupled Zakharov’s equations describe the weakly nonlinear interaction of em wave perturbation with electron acoustic waves while propagating through plasma. In the low frequency or adiabatic limit, these Zakharov’s equations may be unified to produce a modified NLSE. A solution of the equation, novel in the literature, is derived following the method shown by Kudryashov. In a resonant regime, the modified NLSE reduces to NLSE. Though a stable solution exists for both cases, instability analysis shows caviton instability may arise. The threshold value of the electric field, at which instability sets in, is virtually zero for the resonant region whereas, apart from that region there is a threshold value of the electric field, determined by the frequency difference of em wave and electron plasma wave. Experimental observations support these results. This study is relevant for laser-plasma interaction and astrophysical and space plasma.

The impact of quantized magnetic pressure on the stimulated Brillouin scattering of electromagnetic waves

Within the frame work of Landau quantization theory of Fermi gas, we formulate here the exotic physics of magnetic stimulated Brillouin scattering instability (MSBS) arising due to the nonlinear interaction of high frequency electromagnetic waves (EMWs) with degenerate, strongly magnetized electron-ion plasma. Quantum magneto hydrodynamic model (QMHD) is followed to develop the basic differential equations of quantized magnetosonic waves (QMWs) in the presence of super strong magnetic (SSH) field, whereas Maxwell equations are used to derive the governing differential equation of pump EMWs. The nonlinear interaction of EMWs and QMWs is addressed by employing the phasor matching technique. The obtained dispersion relation of MSBS shows that for a fixed density of fermions, the SSH field alone suppresses the MSBS instability as a function of quantized magneto ion velocity (C He ) and the Alfven speed (V A ) via three-wave decay and modulational instabilities. However, for particular condition the MSBS instability is found to increase as a function of SSH field. Next, the analytical results are verified numerically and graphically for soft x-rays in the environment of neutron star. The present MSBS analysis may be critical in neutron stars, radio pulsars and magnetars having super strong magnetic field i.e. even larger than the quantum threshold value i.e, H ∼ 4.4 × 1013 G, or in any application where the enhancement or suppression of SBS may be important.

Signatures of quantized magnetic field on the nonlinear Landau damping of transverse electromagnetic waves

A quantum kinetic approach alongwith the Landau theory of quantization (LQ) is utilized to study the impact of the magnetic field on the nonlinear Landau damping (NLD) of transverse electromagnetic (EM) waves in a degenerate electron-ion plasma. The gyratory motion of fermions around the magnetic field (H) lines gets quantized into the Landau levels and consequently the associated Fermi–Dirac distribution function becomes modified with the fermion cyclotron frequency under the limit l ℏ ω ce − ε Fe ≫ k B T e , where l is the orbital quantum number with all other standard notations. In this context, the density oscillations due to electrons are calculated in the presence of the LQ parameter η( = ℏ ω ce /ε Fe < 1) and ion density perturbations are computed using the framework of Maxwell distribution. A new type of kinetic nonlinear Shrödinger equation is derived in the presence of η, which involves nonlocal nonlinear term responsible for the NLD of EM waves. Furthermore, longitudinal wave modes are investigated to account for quantization parameter η. The LQ is also shown to absorb oscillation spectra of the linear ion-acoustic mode. The present findings might be helpful to understand the impact of the H field on the nonlinear interaction of EM waves with astrophysical plasmas, e.g., in the atmosphere of neutron star the presence of quantized magnetic field is more common.

Nonlinear Electromagnetic-wave Interactions in Pair Plasma. I. Nonrelativistic Regime

High brightness-temperature radiation is observed in various astrophysical sources: active galactic nuclei, pulsars, interstellar masers, and flaring stars; the discovery of fast radio bursts renewed interest in the nonlinear interaction of intense radiation with plasma. In astronomical systems, the radiation frequency is typically well above the plasma frequency and its spectrum is broad, so nonlinear processes differ considerably from those typically studied in laboratory plasma. This paper is the first in a series devoted to the numerical study of nonlinear interactions of electromagnetic waves with plasma. We start with nonmagnetized pair plasmas, where the primary processes are induced (Compton) scattering and filamentation instability. In this paper, we consider waves in which electron oscillations are nonrelativistic. Here, the numerical results can be compared to analytical theory, facilitating the development of appropriate numerical tools and framework. We distill the analytic theory, reconciling the plasma and radiative transfer pictures of induced scattering and developing in detail the kinetic theory of modulation/filamentation instability. We carry out homogeneous numerical simulations using the particle-in-cell codes EPOCH and Tristan-MP for both monochromatic waves and wave packets. We show that simulations of both processes are consistent with theoretical predictions, setting the stage for analyzing the highly nonlinear regime.

Novel features of electromagnetic waves in an isotropic degenerate electron-ion plasma

Within the framework of kinetic theory, the nonlinear interaction of electromagnetic waves (EMWs) with a degenerate electron-ion plasma is studied to account for the electron quantum mechanical effects. For this purpose, a specific quantum regime is considered, for which the degenerate electron Fermi velocity is assumed to be of the order of the group velocity of EMWs. This eventually leads to the existence of a nonlinear Landau damping rate for the EMWs in the presence of electron ponderomotive force. The electron–ion density oscillations may have arisen from the nonlinear interaction of EMWs, leading to a new type of nonlinear Schrödinger equation in terms of a complex amplitude for electromagnetic pump waves. The profiles of nonlinear damping rates reveal that EMWs become less damped for increasing the quantum tunneling effects. The electrostatic response of the linear electrostatic waves is also investigated and derived from a linear dispersion for the ion-acoustic damping rate. The latter is a direct function of the electron Fermi speed and does not rely on the Bohm tunneling effect. The obtained results are numerically analyzed for two microwaves of different harmonics in the context of nonrelativistic astrophysical dense plasma environments, e.g. white dwarfs, where the electron quantum corrections cannot be ignored.

Hodograph solutions of the wave equation of nonlinear electrodynamics in the quantum vacuum

The process of photon-photon scattering in vacuum is investigated analytically in the long-wavelength limit within the framework of the Euler-Heisenberg Lagrangian. In order to solve the nonlinear partial differential equations (PDEs) obtained from this Lagrangian use is made of the hodograph transformation. This transformation makes it possible to turn a system of quasilinear PDEs into a system of linear PDEs. Exact solutions of the equations describing the nonlinear interaction of electromagnetic waves in vacuum in a one-dimensional configuration are obtained and analyzed.

Raman and Brillouin scattering instabilities of transverse electromagnetic waves in degenerate electron-ion plasmas

By applying the Maxwell and quantum hydrodynamic equations, we have studied the parametric instabilities of stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS) in an unmagnetized electron-ion quantum plasma. In this context, we have derived the nonlinear dispersion relations of the large-amplitude electromagnetic (EM) waves, the electrostatic electron plasma waves, and the ion-acoustic waves. The nonlinear evolution equations are then solved by utilizing the Fourier transform to obtain expressions for the three-wave decay and modulational instabilities with quantum corrections. It is found that the growth rate of the instabilities is a strong function of large-amplitude EM waves, and quantum effects due to Fermi pressure and quantum correlations stabilize both SRS and SBS instabilities. Expressions for the maximum growth rates attributed to SRS and SBS instabilities are also derived by ignoring the nonlinear correction shift on the frequency of EM waves. The relevance of nonlinear interaction of EM waves with a quantum dense astrophysical plasma is highlighted in the perspective of electron Fermi pressure and exchange-correlation effects, where the plasma density is high enough.

Nonlinear interaction of electromagnetic waves with 3-component relativistic quantum plasma

The interaction of intense circularly polarized electro-magnetic (CPEM) wave with 3-component relativistic-quantum plasma consisting of relativistic-degenerate electrons and positrons, and dynamic degenerate ions is theoretically studied. A mathematical model is structured by coupling Klein-Gordon equations for the electrons and positrons, and Schrödinger equation for the ions with Maxwell equations through Poisson equations. The solutions of the dispersion relation are plotted for relativistic quantum plasma in the density-range of ∼1030→1036m−3 for several positron concentrations. Three wave modes are observed: electrons, ions, and positrons. The pair branch mode having a possible association with the positron states stays unaltered by variation in the positron concentration but varies significantly with a change in the quantum parameter defined in terms of the particles number density. The addition of positron to the plasma and increasing the positron concentration suggest enhancement of the opacity of the relativistic quantum plasma. The nonlinear interaction of large amplitude CPEM waves with the plasma leads to self-induced transparency. The transparency decreases with increasing positron concentration. The model so developed is then applied to study stimulated Raman scattering, modulational instability, and stimulated Brillouin scattering of intense CPEM waves in such plasmas. The results show that the growth rates are affected by the positron concentration, the quantum parameter of the plasma, as well as by the amplitude of the incident electromagnetic wave.

On the design of experiments for the study of extreme field limits in the interaction of laser with ultrarelativistic electron beam

We propose the experiments on the collision of laser light and high intensity electromagnetic pulses generated by relativistic flying mirrors, with electron bunches produced by a conventional accelerator and with laser wake field accelerated electrons for studying extreme field limits in the nonlinear interaction of electromagnetic waves. The regimes of dominant radiation reaction, which completely changes the electromagnetic wave-matter interaction, will be revealed in the laser plasma experiments. This will result in a new powerful source of ultra short high brightness gamma-ray pulses. A possibility of the demonstration of the electron-positron pair creation in vacuum in a multi-photon processes can be realized. This will allow modeling under terrestrial laboratory conditions neutron star magnetospheres, cosmological gamma ray bursts and the Leptonic Era of the Universe.

Nonlinear Phenomena in Magnetic Nanoparticle Systems at Microwave Frequencies

Nonlinear interactions of electromagnetic waves (EMW) in magnetic nanoparticle systems at microwave frequencies were numerically simulated using rigorous mathematical models to solve the nonlinear diffraction boundary problem. The transmission coefficients |S12| of arrays of ferrite spheres, depending on the normalized frequency omega/gamma (gamma gyromagnetic ratio), for radii of 250 mm and 0.1 mm, and separation between the spheres from 600 to 3000 nm, were determined. The increase of the interaction effects upon decreasing separation is demonstrated. The instability regions of parametric generation in the nonlinear ferrite sphere array, depending on the magnitude of the pumping wave at frequency omegaH, are simulated using our computational algorithm of the bifurcation points of the nonlinear Maxwell's operator. With decreasing separation, i.e., increasing interaction between the spherical elements of the array, the instabilities occur at lower inputs, revealing the power sensitivity of small particle systems.

Transformation of sinusoidal electromagnetic and polarization waves into cnoidal waves in an optical fibre

Abstract It is shown that a sinusoidal signal wave can transform into a cnoidal (periodic) wave in an optical fibre if the power signal propagates in the fibre core. In this case the signal wave period increases, but the wave profile does not almost change. The signal wave gets the form of kink for the high-power signal. The wave transformation is determined by nonlinear effects in the fibre core. The lin-ear modes of the fibre transform into the nonlinear ones under influence of cubic or higher nonlinear interactions of electromagnetic and polarization waves. These changes are described by the equation with sinusoidal nonlinearity for the polarization wave. The approximate and exact analytical solutions of the nonlin-ear equation are obtained. PACS: 42.65.-k, 42.65.Wi UDC: 535.3 Keywords: optical fibre, polariton, cnoidal wave, kink Introduction Nowadays optical fibres have become basic media for transmitting information streams. The more information you transfer the higher power of input signals you deal with. As a result, nonlinear interactions of electromagnetic waves and dielectric medium can take place in the core of optical fibre. The critical value of intensity needed for appearance of nonlinear polarization waves is

Dimensional Resonances and Second-Harmonic Generation in a Semibounded Nonlinear Layered Periodic Medium

A theory for the nonlinear interaction of electromagnetic waves in a semibounded periodic dielectric structure is developed using the example of second-harmonic generation. One of the layers forming a period is assumed to have nonlinear polarization. The theory is an improved perturbation theory based on the Green theorem. The phase-matching conditions for interacting waves are shown to correspond to dimensional resonances for individual layers or for the structure period. The interaction efficiency is maximum at passband edges for the case of resonance for the entire period. For this resonance, the phase-matching conditions are met for a frequency spectrum rather than for a single frequency. This feature makes it possible to convert spectra from one frequency range to another.

Interaction of intense laser radiation with weak electromagnetic waves in an evacuated section of a ring laser

A laboratory experiment for the study of nonlinear interaction of electromagnetic waves in vacuum is proposed. The basic idea of the experiment is as follows. If one separates a certain region of the circuit in a ring laser from the remaining part with gas-impenetrable partitions, evacuates it, and forms external electromagnetic fields there, the oscillation frequencies and the polarization states of the electromagnetic waves traveling in this ring laser in counter directions are different. A calculation is made for the oscillation frequencies of electromagnetic waves traveling in a ring laser in opposite directions in the case when they interact in an evacuated section of the ring laser circuit with intense laser radiation. It is shown that the effect can be observed in experiments using presently available pulsed lasers of ultrahigh power.

Stimulated transparency of a superconducting plate caused by nonlinear interaction of electromagnetic waves

A nonlinear effect in the electrodynamics of hard superconductors is predicted and theoretically studied. It is shown, that a low-frequency (LF) electromagnetic wave can pass through a superconducting plate, due to its interaction with another wave propagating in the opposite direction, even at small amplitudes of the LF wave when it cannot reach the opposite boundary of the sample without assistance. The dependence of the LF surface impedance on the amplitude of the high-frequency (hf) wave is studied within the framework of the critical state model. The LF surface impedance is found to be drastically increased by the overlapping of the regions of wave penetration.

Linear and nonlinear interaction of electromagnetic waves with weakly ionized magnetized plasmas

We derive the basic equations for magnetoacoustic hydrodynamics (MAD). A new branch of electromagnetic waves having small damping is obtained in the range of the electron cyclotron frequency in a strong collisional plasma. Filamentational and modulational instabilities are elaborated. The effect of helicon waves (whistlers) on the plasma is considered and instabilities are studied. The formation of solitons and shock waves is investigated.

Features of the nonlinear interaction of electromagnetic waves in HTSC ceramics

The nonlinear interaction of electromagnetic waves in an HTSC plate in the critical state is studied both theoretically and experimentally. The magnetic components of both waves are collinear and parallel to the plate surface. We have considered two radiowaves having different frequencies and have predicted and experimentally observed jumps of the electrical field E(t) on the plate surface which take place owing to the nonlinear wave interactions. Besides, we have investigated the behaviour of the nonlinear surface impedance at low frequencies as a function of the radiowave amplitudes. The unusual non-monotonous dependence of the surface impedance (both real and imaginary components) on the radiowave amplitudes has been obtained. The character of the magnetic field dependence of the critical current density significantly influences the lineshape of the E(t) curves. Therefore, one can obtain information on this dependence from the results of E(t) measurements.

Nonlinear interaction of photons and phonons in electron-positron plasmas.

Nonlinear interaction of electromagnetic waves and acoustic modes in an electron-positron plasma is investigated. The plasma of electrons and positrons is quite plastic so that the imposition of electromagnetic (em) waves causes depression of the plasma and other structural imprints on it through either the nonresonant or resonant interaction. Our theory shows that the nonresonant interaction can lead to the coalescence of photons and collapse of plasma cavity in higher (\ensuremath{\ge}2) dimensions. The resonant interaction, in which the group velocity of em waves is equal to the phase velocity of acoustic waves, is analyzed and a set of basic equations of the system is derived via the reductive perturbation theory. We find new solutions of solitary types: bright solitons, kink solitons, and dark solitons as the solutions to these equations. An implication of the present theory on astrophysical plasma settings is suggested, including the cosmological relativistically hot electron-positron plasma.

Nonlinear interaction of electromagnetic waves in superlattices

Nonlinear interaction of electromagnetic waves in superlattices

Comments on “Nonlinear Interaction of Electromagnetic Waves in a Cold Magnetized Plasma”

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Nonlinear interaction of electromagnetic waves in bounded plasmas

A method is presented for the solution of second-order electromagnetic fields in a bounded plasma which is excited by two high-frequency electromagnetic waves. Due to nonlinearities inherent in any plasma, incoming waves are mixed, creating sum and difference frequencies. The signal from the difference frequency \omega_{1}-\omega_{2} , where \omega_{1} and \omega_{2} are source frequencies, can be of considerable consequence when \omega_{1}-\omega_{2} is sufficiently low to cause a significant reaction in a plasma as resonant conditions develop. In particular, the problem considered in this paper is the optimization of second-order fields in a uniform plasma confined to a circular waveguide including reference to diagnostic applications.