Homogeneous Magnetized Plasma Research Articles

Kinetic effects of dust size distribution on Alfvén waves in magnetized space plasmas

ABSTRACT Dust populations in space plasmas are often described by a size distribution function, generally a power law distribution. In view of that, we include this feature in the kinetic description of a homogeneous magnetized dusty plasma with electrically charged immobile dust grains, in order to study its effects in the propagation and damping of Alfvén waves. The dispersion relation is numerically solved using parameters typically found in the dust-driven stellar winds of carbon-rich stars and in Earth’s auroral acceleration region, two space systems with unalike plasma parameters and in which Alfvén waves are known to play important roles in the plasma acceleration and heating processes. We show that the characteristics of the normal modes, namely the ion cyclotron and whistler modes, will change when one considers a power law distribution of dust sizes in the theory, as compared to a mono-sized dust population; and that these differences will depend on the exponent p of the power law, which alters the plasma charge imbalance between electrons and ions. We also notice that power-law distribution functions will modify the waves’ damping rate values. In particular, we show that in a stellar wind environment the ion cyclotron mode at very small wavenumber decreases with the reduction of p, while for higher wavenumber the damping of this mode increases with the reduction of p. For the Earth’s magnetosphere, the results obtained show that the wave damping increases with the decrease of p for all wavenumbers, for the parameters considered in the analysis.

Ion Acoustic Solitary Wave Solutions to mKdV-ZK Model in Homogeneous Magnetized Plasma

In this exploration, we reflect on the wave transmission of three-dimensional (3D) nonlinear electron–positron magnetized plasma, counting both hot as well as cold ion. Treated equation acquiesces to nonlinear-modified KdV-Zakharov–Kuznetsov (mKdV-ZK) dynamical 3D form. The model is integrated by the φ 6 -model expansion scheme and invented few families of ion acoustic solitonic propagation results in term of Jacobi elliptic functions. Various shock waves, bullet like bright soliton, dark soliton, singular soliton, as well as periodic signal solutions, are formed from the Jacobi elliptic solution for different parametric constraints. Some of the solutions are illustrated graphically and analyzed width and height due to change of exist parameters in the solutions. Figures are provided to explain the wave natures and effects of nonlinear and fractional parameters are presented in the same two-dimensional (2D) plots.

On the force exerted on a non-spherical dust grain from homogeneous magnetized plasma

It is shown that stationary non-spherical dust grains immersed into stationary magnetized plasma can experience the j → × B → force due to electric current flowing through the grain. The electric current can be caused by different patterns of electron and ion fluxes impinging on the grain.

Effects of dust particles charged by inelastic collisions and by photoionization on Alfvén waves in a stellar wind

ABSTRACT Using a kinetic description of a homogeneous magnetized dusty plasma with Maxwellian distribution of electrons and protons and dust particles charged by inelastic collisions and by photoionization, we analyse the dispersion relation considering the case where waves and radiation propagate exactly parallel to the ambient magnetic field. The investigation emphasizes the changes that the photoionization process brings to the propagation and damping of the waves in a stellar wind environment, since Alfvén waves are believed to play a significant role in the heating and acceleration processes that take place in the wind. The results show that, in the presence of dust with negative equilibrium electrical charge, the Alfvén mode decouples into the whistler and ion cyclotron modes for all values of wavenumber, but when dust particles acquire neutral or positive values of electrical charge, these modes may couple for certain values of wavenumber. It is also seen that the whistler and ion cyclotron modes present null group velocity in an interval of small wavenumber, and that the maximum value of wavenumber for which the waves are non-propagating is reduced in the presence of the photoionization process. For very small values of wavenumber, the damping rates of the modes could change significantly from very small to very high values if the sign of the dust electrical charge is changed.

Propagation of a terahertz Bessel vortex beam through a homogeneous magnetized plasma slab

This paper provides an analytic method to study propagation characteristics of a linearly polarized Bessel vortex beam through a homogeneous magnetized plasma slab. The incident Bessel vortex beam, as well as the reflected, transmitted and internal fields are expanded in terms of cylindrical vector wave functions (CVWFs). The effects of plasma thickness, electron density and magnetic induction strength on the contour profiles of the reflected and transmitted beams and orbital angular momentum (OAM) spectra are analyzed and discussed in detail. In particular, the magnetic induction strength has a significant impact on the polarization of the transmitted beam, but not on OAM state distribution. The channel capacity of THz OAM multiplexing decreases with an increase of plasma thickness and electron density.

Nonlinear waves behaviors for a coupled generalized nonlinear Schrödinger–Boussinesq system in a homogeneous magnetized plasma

Under investigation in this paper is a coupled generalized nonlinear Schrodinger–Boussinesq system, which describes the coupled upper-hybrid and magnetoacoustic modes in a homogeneous magnetized plasma for the bidirectional propagation near the magnetoacoustic speed. Based on the Hirota method, the expressions for the multi-soliton solutions are given. Effects of the group velocity, group dispersion coefficient for the upper-hybrid, and the properties of the magnetic field on the soliton are discussed. Based on the asymptotic analysis, interaction between two solitons is proved to be elastic through the asymptotic analysis. Position at which the maximal distortion occurs is obtained. Multi-soliton interaction is illustrated and investigated. Two prerequisites of the formation and features of the bound state are discussed. For the cases of three solitons, inelastic interaction occurs with phase shifts. Characteristics of the breather and its relation with the bound state and the breather are investigated. Interaction between the bound state (even the breather) and a single soliton is discussed for both cases that they are parallel or not.

Photonic Bandgap of Random in Layer Position Extrinsic Magnetized Plasma Multilayer

The transmittance of electromagnetic waves, with normal incidence, in 1-D random extrinsic magnetized plasma photonic structures is studied numerically based on the transfer-matrix method. Here, the homogeneous magnetized plasma having a uniform density profile is considered. Continuing a previous study [IEEE T. Plasma Sci., vol. 47, no. 4, pp. 1726–1733, 2019], we investigate how the main photonic bandgap in an extrinsic magnetized plasma photonic structure changes when the positions of the layers in the entire structure are random. The numerical calculations show that a robust photonic bandgap can be realized up to a certain probability of occurrence. Also, we show that the proposed random multilayered structure can work as a robust tunable photonic lattice which can be controlled by the plasma parameters and the external magnetic field.

The RCS of the 3-D conductor sphere calculated in THz band and the homogeneous magnetized dense plasma sheath

The reentry vehicle of high speed has serious friction with the gas surrounding themselves which leads to a high temperature and high level of ionized of neutral particles thus forming a plasma sheath with a high plasma frequency and collision frequency. Microwave can’t penetrate it and arrive at the vehicle, correspondingly, the communication is cut off. Therefore, the radar cross section (RCS) of the conductor sphere in THz band is calculated to illustrate the strong penetration ability of the THz wave in a dense plasma sheath. The scattering characteristics in dense, magnetized plasma sheath is studied using the Finite-Difference Time-Domain method based on the Runge-Kutta Exponential Time Differencing formulation (RKETD-FDTD). 3-D conductor sphere model is established and the amount of the bistatic RCS is displayed in the polar coordinates. Influences on it caused by the direction of the magnetic field, the collision frequency, the frequency of plasma, the included angle between the incident wave and z coordinate axis and the polarized direction are discussed in detail. By comparing with the RCS in the no coating simulation conditions, it demonstrates that THz wave have a better penetration effect and may be chosen as an effective solution to the ‘black out’ problem.

Cutoff frequencies of accelerating modes propagation inside a cylindrical waveguide filled with radially inhomogeneous magnetized plasma

The cutoff frequencies of accelerating hybrid EH0l mode (l = 1, 2, 3, and 4) propagation are studied in a cylindrical waveguide filled with radially inhomogeneous plasma in the presence of an external static magnetic field applied along the waveguide axis. To drive the analytical cutoff equations, a model based on the Bessel-Fourier expansion, which considers strong spatial dispersion and a finite external magnetic field, is utilized. In order to examine the integrity of the cutoff equations, the well-known cutoff expression related to the hybrid EH wave in a homogeneous magnetized plasma waveguide is recalculated with the help of a new model. The cutoff equations are solved numerically, and the effects of the external magnetic field and plasma density are investigated on the cutoff frequencies of the EH0l modes (l = 1, 2, 3, and 4) in the particular waveguide with a radius of 2.1 cm. By studying the effect of the waveguide radius on the cutoff frequencies, it is revealed that the waveguide radius plays a decisive role in the behavior of the cutoff frequencies with the external static magnetic field and plasma density. It is found that a critical radius can be realized for the waveguide so that the cutoff frequency treatment with the external magnetic field and plasma density is reversed in it.

FDTD Analysis of Propagation and Absorption in Nonuniform Anisotropic Magnetized Plasma Slab

In this paper, a current density convolution finite-difference time-domain method is extended to study the electromagnetic wave propagation and absorption in inhomogeneous magnetized plasmas. First of all, we analyze the wave propagation in homogeneous magnetized plasmas for arbitrary magnetic inclination angle. Then, we studied three types of plasma absorption, including plasma resonance, electron cyclotron resonance, and upper hybrid resonance in homogeneous and inhomogeneous magnetized plasmas. This model is applied to simulate the heating mechanism during ionospheric modification experiments by high-power high-frequency radio waves. These results have important implications for the interpretation of physical mechanisms for the interaction of high power radio waves with magnetized ionospheric plasmas and design of future experiments.

Energy behaviour of extraordinary waves in magnetized quantum plasmas

We study the storage and flow of energy in a homogeneous magnetized quantum electron plasma that occurs when an elliptically polarized extraordinary electromagnetic wave propagates in the system. Expressions for the stored energy, energy flow, and energy velocity of extraordinary electromagnetic waves are derived by means of the quantum magnetohydrodynamics theory in conjunction with the Maxwell equations. Numerical results show that the energy flow of the high-frequency mode of extraordinary wave is modified only due to the Bohm potential in the short wavelength limit.

Quasi-soliton solution of Korteweg-de Vries equation and its application in ion acoustic waves

Investigation of interaction between solitons and their background small amplitude waves has been an interesting topic in numerical study for more than three decades. A classical soliton accompanied with oscillatory tails to infinite extent in space, is an interesting quasi-soliton, which has been revealed in experimental study and really observed. However, analytical solution of such a special quasi-soliton structure is rarely considered. In this paper, two branches of soliton-cnoidal wave solution as well as the two-soliton solution of the Korteweg-de Vries (KdV) equation are obtained by the generalized tanh expansion method. The exact relation between the soliton-cnoidal wave solution and the classical soliton solution of the KdV equation is established. By choosing suitable wave parameters, the quasi-soliton behavior of the soliton-cnoidal wave solution is revealed. It is found that with modulus of the Jacobi elliptic function approaching to zero asymptotically, the oscillating tails can be minimized and the soliton core of the soliton-cnoidal wave turns closer to the classical soliton solution. In addition, the quasi-soliton structure is revealed in a plasma physics system. By the reductive perturbation approach, the KdV equation modeling ion acoustic waves in an ideal homogeneous magnetized plasma is derived. It is confirmed that the waveform of the quasi-soliton is significantly influenced by the electron distribution, temperature ratio of ion to electron, magnetic field strength, and magnetic field direction. Interestingly, the amplitude of the quasi-soliton keeps constant due to the -independence of nonlinear coefficient A. The width of the soliton core and the wavelength of the surrounded periodic wave become constant with the further increase of . The explicit soliton-cnoidal wave solution with quasi-soliton behavior obtained here is applicable to many physical scenarios. For instance, the quasi-soliton structure can be viewed as a classical soliton with perturbations, and can correct the classical soliton in both theoretical and experimental study.

Raman scattering of circularly polarized laser beam in homogeneous and inhomogeneous magnetized plasma channel

Raman scattering of circularly polarized laser beams in a magnetized plasma channel is investigated. The scattering is considered as parametric instability. Dispersion relations of backward and forward scattered waves in a magnetized plasma are derived in a weakly relativistic regime. Growth rates of the corresponding instabilities are calculated. The effects of laser intensity and its polarization as well as the strength of the magnetic field and corresponding cyclotron frequency along with plasma density and its inhomogeneity on the growth rate of Raman scattering are examined. The study shows that the left-handed circularly polarized laser beam has different behaviors in comparison to the right-handed beam, and their growth rates are different due to the anisotropic properties of the magnetized plasma. In addition, Raman scattering in an inhomogeneous plasma with a linear density profile is investigated. The comparison between homogeneous and inhomogeneous plasmas has indicated that inhomogeneity reduces the growth rate. The frequency shift of scattered waves, when laser intensity is high, is studied in the magnetized plasma. The findings indicate that the shift depends on laser intensity and its polarization as well as plasma density and dc magnetic field. The frequency shift can be used as a diagnostic tool for density measurement in laser-plasma interactions.

Effect of rotation on Jeans instability of magnetized radiative quantum plasma

The influence of rotation on the Jeans instability of homogeneous magnetized radiative quantum plasma is investigated. The basic equations of the problem are constructed and linearized by using the Quantum Magnetohydrodynamics (QMHD) model. The general dispersion relation is obtained by using the normal mode analysis technique, which is reduced for both the transverse and the longitudinal mode of propagations and further it is reduced for the axis of rotation parallel and perpendicular to the magnetic field. We found that the stabilizing effects of rotation are decreases for a strong magnetic field which is shown in the graphical representation. We also found that the quantum correction modified the condition of Jeans instability in both modes of propagation. The stabilizing effect of rotation is more increased in the presence of quantum correction.

Study on the properties of photonic band gap and flatbands in the three-dimensional magnetized plasma photonic crystals with a general case

In this paper, the properties of photonic band gap (PBG) and flatbands in the three-dimensional (3D) magnetized plasma photonic crystals (MPPCs) with a general case in face-centered-cubic lattices are theoretically investigated based on the modified plane wave expansion method, in which the homogeneous magnetized plasma spheres are immersed in the homogeneous and isotropic dielectric background, as the magneto-optical Faraday effects are considered. The more general situation has been considered, and the PBG of such MPPCs is for all of the electromagnetic waves. The derivation of the formulas for calculating also is given. Theoretical computing results show that a PBG and two flatbands regions can be obtained. Compared to the conventional dielectric-air photonic crystals with similar structure, the larger PBG can be obtained in such 3D MPPCs. However, the narrower PBG can be achieved compared to that for the right circular polarized (RCP) wave, and the larger upper edge frequency of second flatbands region can be achieved. For the flatbands region, the upper edge only can be tuned by the plasma frequency and plasma cyclotron frequency. The effects of plasma frequency and plasma cyclotron frequency (the external magnetic field) on the properties of PBG also are investigated theoretically in detail. Theoretical simulations show that the PBG can be manipulated by those two parameters. The results show that the properties of PBG are obviously different with those for RCP wave in the similar 3D MPPCs. Those results can hold promise for opening a new scope to design the filters, planar reflectors, omnidirectional mirrors, absorber or waveguides based on the 3D MPPCs.

Gyro-viscosity and linear dispersion relations in pair-ion magnetized plasmas

A fluid theory has been developed by taking account of gyro-viscosity to study wave propagation characteristics in a homogeneous pair-ion magnetized plasma with a cylindrical symmetry. The exact dispersion relations derived by the Hankel-Fourier transformation are shown comparable with those observed in the experiment by Oohara and co-workers. The gyro-viscosity is responsible for the change in propagation characteristics of the ion cyclotron wave from forward to backward by suppressing the effect of the thermal pressure which normally causes the forward nature of dispersion. Although the experiment has been already explained by a kinetic theory by the present authors, the kinetic derivations are so involved because of exact particle orbits in phase space, finite Lamor radius effects, and higher order ion cyclotron resonances. The present fluid theory provides a simple and transparent structure to the dispersion relations since the gyro-viscosity is renormalized into the ion cyclotron frequency which itself indicates the backward nature of dispersion. The usual disadvantage of a fluid theory, which treats only fundamental modes of eigen-waves excited in a system and is not able to describe higher harmonics that a kinetic theory does, is compensated by simple derivations and clear picture based on the renormalization of the gyro-viscosity.

Nonlinear oscillatory and monotonic shocks in dense plasmas with ultra-relativistic degenerate electrons

In this paper we study the ion acoustic oscillatory and monotonic shocks in dissipative homogeneous magnetized plasmas. The dissipation in the plasma system is considered via kinematic viscosity of ions and quantum effects are included through degeneracy pressure of ultra-relativistic electrons. Korteweg de Vries Burgers (KdVB) equation is derived by using reductive perturbation method. Numerical and analytical solutions of KdVB equation are presented. The transition from oscillatory profile to monotonic shock are studied numerically at different values of kinematic viscosity. We also analyzed the effects of variations of different plasma parameters on the strength of the shock structure in dense plasmas. The relevance of the work to astrophysical plasma conditions such as in compact stars is also pointed out.

Study on the magneto-optical Faraday effects in the properties of anisotropic photonic band gaps and surface plasmon modes for the three-dimensional magnetized photonic crystals as the mixed polarized waves considered

In this paper, the magneto-optical Faraday effects in the properties of anisotropic photonic band gaps (PBGs) and surface plasmon modes for the three-dimensional (3D) magnetized plasma photonic crystals (MPPCs) with body-centered cubic lattices are theoretically studied based on the modified plane wave expansion (PWE) method, in which the homogeneous Te (tellurium) spheres are immersed in the homogeneous magnetized plasma background, as the mixed polarized waves are considered. A more general case is investigated, and the anisotropic PBGs are not only for the left- and right-circular polarized waves but also for the mixed polarized waves. The equations for computing those anisotropic PBGs for all of the electromagnetic waves in such 3D MPPCs are theoretically deduced. Theoretical simulations show that the anisotropic PBGs and a flatbands region can be observed. Compared to the similar 3D MPPCs containing the isotropic dielectric or uniaxial material spheres, the largest PBG can be obtained as the extraordinary axis of inserted uniaxial material is along the Г-H symmetry line. The larger PBGs can also be achieved compared to the conventional PBGs for the right-circular polarized wave as the mixed polarized waves are considered. The interesting properties of surface plasmon modes can also be found, which are the upper edge of flatbands region cannot be tuned by the filling factor but almost can be linearly increased with increasing the plasma frequency and plasma cyclotron frequency, respectively. The effects of the filling factor, plasma frequency, and plasma cyclotron frequency (the external magnetic field) on the anisotropic PBGs are also investigated in detail. Theoretical simulations also show that such PBGs can be manipulated by the parameters as mentioned above.

The properties of photonic band gap and surface plasmon modes in the three-dimensional magnetized photonic crystals as the mixed polarized modes considered

In this paper, the properties of photonic band gap (PBG) and surface plasmon modes in the three-dimensional (3D) magnetized plasma photonic crystals (MPPCs) with face-centered-cubic (fcc) lattices are theoretically investigated based on the plane wave expansion (PWE) method, in which the homogeneous magnetized plasma spheres are immersed in the homogeneous dielectric background, as the Voigt effects of magnetized plasma are considered (the incidence electromagnetic wave vector is perpendicular to the external magnetic field at any time). The dispersive properties of all of the EM modes are studied because the PBG is not only for the extraordinary and ordinary modes but also for the mixed polarized modes. The equations for PBGs also are theoretically deduced. The numerical results show that the PBG and a flatbands region can be observed. The effects of the dielectric constant of dielectric background, filling factor, plasma frequency and plasma cyclotron frequency (the external magnetic field) on the dispersive properties of all of the EM modes in such 3D MPPCs are investigated in detail, respectively. Theoretical simulations show that the PBG can be manipulated by the parameters as mentioned above. Compared to the conventional dielectric-air PCs with similar structure, the larger PBG can be obtained in such 3D MPPCs. It is also shown that the upper edge of flatbands region cannot be tuned by the filling factor and dielectric constant of dielectric background, but it can be manipulated by the plasma frequency and plasma cyclotron frequency.

Hamiltonian models for resonant wave-particle interaction processes in magnetized and inhomogeneous plasmas

The kinetic theory of plasmas, based on the Vlasov-Poisson system of equations, can efficiently solve only some aspects of the extremely large panel of problems involving wave-particle and wave-wave interaction processes in plasmas. Therefore the dynamics of charged particles and waves has been modeled by other approaches as, for example, Hamiltonian models describing the self-consistent wave-particle and wave-wave interactions in homogeneous or inhomogeneous magnetized plasmas. Various physical problems could be efficiently studied by such methods, concerning nonlinear and turbulent stages of different instabilities of electron or ion distributions, wave packets’ saturation and particles fluxes’ relaxation processes, particle trapping and detrapping mechanisms by waves, wave-particle interactions at multiple resonances, quasilinear diffusion processes of particles in waves, wave turbulence in randomly inhomogeneous plasmas, acceleration of particles, wave focusing, scattering, reflection and decay, etc. In particular, the aim of the paper, after a brief description of such Hamiltonian models, is to present the most recent simulation results obtained when studying Langmuir turbulence in the presence of electron beams propagating in inhomogeneous plasmas as the solar wind, where random density fluctuations with average levels up to several percents of the background plasma density have been measured.