Acoustic Solitons Research Articles

Propagation and Collision Phenomena of Ion Acoustic ZK Solitons in Quantum Plasmas: Effects of External Force and Exchange–Correlation Potential of Degenerate Electrons

Propagation and Collision Phenomena of Ion Acoustic ZK Solitons in Quantum Plasmas: Effects of External Force and Exchange–Correlation Potential of Degenerate Electrons

Cubic nonlinearity driven dust ion acoustic solitons with superthermal two-temperature electrons in the Saturn’s magnetosphere

Nonlinear propagation of electrostatic waves with cubic nonlinearity has been investigated in a multicomponent dusty plasma with inertial ions, superthermal two temperature electrons and stationary dust. In this regard, single and multi-soliton solutions of modified Korteweg–de Vries (mKdV) equation for dust ion acoustic waves (DIAWs) have been investigated implementing Hirota’s bilinear method. Plasma parameters affecting the amplitude of dust ion acoustic (DIA) mKdV single soliton have been thoroughly investigated based on the data from Saturn’s magnetosphere. The overtaking interaction of two mKdV solitons has been investigated by changing the percentage of propagation vectors to observe bipolar structure reducing to a single humped structure for a particular value of the ratio of propagation vectors. The most significant outcome of this study has been the investigation of interaction of a compressive and rarefactive dust ion acoustic soliton forming a peculiar composite shape at the interaction point.

Study of cylindrical and spherical dust acoustic solitons and quasiperiodic structures in a quantum dusty plasma

The solitonic and quasiperiodic structures of dust acoustic (DA) waves are investigated in a three components quantum dusty plasma composed of mobile negative dust grains, ions, and inertialess electrons. The reductive perturbation method is employed to derive A deformed Korteweg–de Vries (dKdV) equation in planar and nonplanar geometries, and its numerical solutions are obtained using the two level finite difference approximation method. The influence of geometries on DA solitons is discussed. It is observed that in nonplanar geometries, DA solitons travel at different speeds in comparison to one-dimensional planar ones. Furthermore, in the planar geometry, the bifurcation of DA traveling waves has been analyzed on the framework of the dKdV equation. By adding an external periodic force to the derived dKdV equation, the quasiperiodic behaviors of DA waves are presented.

Dust Acoustic Dressed Solitons in Jovian Magnetosphere

In this investigation, the evolution of dust acoustic solitons (DASs) and dust acoustic dressed solitons (DADSs) have been examined in the Jovian magnetosphere. A five components plasma in which positive dust grains interact with solar wind protons, superthermally distributed electrons, ions as well as solar wind electrons is considered to explore the formation of different kinds of nonlinear structures in the Jovian magnetosphere. The Korteweg-de Vries (KdV) and inhomogenous KdV-type equations encompassing the higher-order (HO) nonlinear and dispersion (N&D) effects are derived by employing the reductive perturbation technique (RPT). With the incorporation of HO effects, a new kind of DADSs are evolved. The influence of various plasma parameters viz., superthermality of ions as well as electrons, temperature, and concentration of different species on the salient features of DASs and DADSs has been encapsulated. The findings of this work may be useful to elucidate the formation of nonlinear dust acoustic coherent structures in the Jovian magnetosphere.

Explicit, periodic and dispersive soliton solutions to the Schamel-KdV equation with constant coefficients

In plasma physics, the Schamel–Korteweg-de Vries (S-KdV) model determines the electrostatic potential for a given electron distribution in velocity space and is used to explore ion acoustic solitons during the trapping of electrons. The key model reduces to the generalised KdV equation for α=0, and the Schamel equation when β=0. In this article, some new traveling wave solutions to the Schamel-KdV equation are constructed with the help of the classical Khater and the modified Khater methods. The observed results are very encouraging, which provide more powerful mathematical tool for analyzing exact traveling wave solution to the nonlinear equations arising in the recent era of applied sciences and engineering.

Collisional positron acoustic soliton and double layer in an unmagnetized plasma having multi-species

This paper explores the head-on collision between two-counter propagating positron acoustic solitons and double layers (DLs) in an unmagnetized collisionless plasma having mobile cold positrons fluid, immobile positive ions and (r,;q)-distributed hot positrons, and hot electrons. By employing the extended Poincaré–Lighthill–Kuo method, the coupled Korteweg–de Vries (KdV), modified KdV (mKdV) and Gardner equations are derived to archive this goal. The effect of dimensionless parameters on the propagation characteristics of interacting KdV solitons (KdVSs), mKdV solitons (mKdVSs), Gardner solitons (GSs) and DLs are examined in detail by considering the limiting cases of (r,;q)-distribution. It is noted that the interaction of GSs and DLs are reported for the first time. The outcomes might be comprehended and beneficial not only in space and astrophysical environments but also in laboratory studies.

Electron acoustic dressed solitons in an electron-beam plasma with higher-order contributions

In this investigation, the evolution of electron acoustic solitons (EASs) and electron acoustic dressed solitons formed due to the contribution of higher-order effects in a superthermal plasma in the presence of an electron beam has been examined. The reductive perturbation method is employed to derive the nonlinear Korteweg–de Vries (KdV) and KdV-type inhomogeneous equations with contribution of higher-order effects of nonlinearity and dispersion. From the solutions of these nonlinear equations, the characteristics of EASs and dressed EASs are analysed under the influence of superthermality of electrons, parameters of an electron beam and other plasma parameters. The findings of present work may be useful to explore and understand the evolution of nonlinear structures in the space and laboratory plasmas especially in Earth’s magnetospheres.

KP, MKP, and CKP dust ion acoustic solitons in a multispecies non-Maxwellian plasma

Characteristics of small amplitude dust ion acoustic (DIA) solitons under transverse perturbations in a multispecies plasma with dust impurity and Vasyliunas–Cairns distributed two temperature electrons are presented. Using a reductive perturbation technique, the Kadomtsev–Petviashivili (KP), modified KP, and coupled KP equations are derived. Furthermore, considering single variable transformation, solutions of different equations are derived to investigate the influence of various plasma parameters and higher order effects on the characteristics of DIA solitons. From the nonlinear coefficient of the KP equation, the parametric range for the existence of positive and negative potential solitons is also determined. Furthermore, the stability analysis of the soliton solution of the KP equation is discussed. It is remarked that all different physical parameters have much influence on the characteristics of different types of small amplitude DIA solitons.

Dust Acoustic Solitons in Saturn\u2019s Dust-Filled Magnetosphere

The possibility is considered of propagation of localized wave structures, such as dust acoustic solitons, in the plasma of the dust-filled Saturn’s magnetosphere, which contains electrons of two sorts (hot and cold) subject to kappa distribution, ions, and charged dust grains. The ranges of possible velocities and amplitudes of the solitons are determined. Soliton solutions for different sizes and concentrations of dust grains in the dust-filled Saturn’s magnetosphere are found.

Interaction of dust ion acoustic solitons with cubic nonlinearity in a magnetized dusty plasma with () distributed electrons

AbstractDust ion acoustic waves (DIAWs) are analysed in multi‐component plasmas via reductive perturbation technique comprising inertial ions, (r, q) distributed electrons, and stationary dust by using fluid theory of plasmas. The modified Kadomtsev‐Petviashvili (MKP) equation is obtained for the critical condition at which the quadratic nonlinearity vanishes. Hirota's bilinear formalism is employed, for the first time, to study the two‐soliton solutions of MKP equation in the context of plasma physics. The effects of flatness at low energy (represented by ) and superthermality at high energy (represented by ) of electrons in phase space are investigated for the linear and nonlinear propagation of DIAWs. It is found that the amplitude of the nonlinear DIAW is highest for the flat‐topped distribution, whereas it is lowest for kappa distribution. Using the plasma parameters of Saturn's B‐ring. The estimates are given of the spatial scales over which the MKP solitons form for flat‐topped, kappa, and Maxwellian distributions, respectively. It is also discussed in detail how the presence of dust and non‐Maxwellian electron distributions affect the interaction of MKP solitons in Saturn's B‐ring. In addition, the interaction of a compressive and rarefactive soliton is studied giving results not achievable for KdV and KP equations.

Dust ion acoustic solitons and double layers in a dusty plasma with adiabatic positive dust, adiabatic positive ion species, and Cairns-distributed electrons

The propagation of dust ion acoustic solitary waves and double layers is studied in a dusty plasma with heavy adiabatic positively charged dust grains and lighter adiabatic positive ions with Cairns-distributed electrons using the arbitrary amplitude Sagdeev pseudopotential approach. The analysis of the Sagdeev pseudopotential shows that this plasma model supports the propagation of positive solitons limited by the occurrence of the ion sonic point and negative solitons limited by the occurrence of double layers. Solitons of both polarities coexist for a range of some plasma parameters. We have shown that at a critical dust-to-ion density ratio, f, at which the third derivative of the Sagdeev pseudopotential vanishes, positive and negative solitons coexist without a soliton with finite amplitude at the acoustic speed, contrary to an earlier study. This suggests that the existence of a soliton with finite amplitude at the acoustic speed is not always a pre-requisite for the coexistence of nonlinear structures of both polarities. Positive and negative solitons coexist when the electrons are strongly nonthermal, with moderate ion thermal effects. Increasing ion thermal effect shifts the coexistence region to lower values of f, and when the ion thermal effects become important, negative solitons disappear and only positive solitons survive. The effects of different plasma parameters on the characteristics of the nonlinear structures have also been discussed in detail.

Cold Fusion Based on Matter-Antimatter Plasma Formed in Molecular Crystals

The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isothermal hydrogen and antihydrogen are injected into a palladium crystal leading to a plasma state composed of particles and antiparticles. The collapse of this state releases a huge amount of energy which can be used as fuel for space shuttles. Thus, the novel system of isothermal pressure interaction enhances the energy power carried out by the quantum ion acoustic soliton (QIAS). In addition to the energy power released from the particle-antiparticle annihilation. The probability of merging the energy from these two cases is available at certain condition. The released energy may be a significant step in solving the energy scape of Tokomak to produce fusion energy. The study starting from the one-dimensional quantum hydrodynamic model (in which the term of electron-positron and proton-antiproton for hydrogen-antihydrogen is included), a Korteweg de Vries equation (kdv) is derived, the QIAS energy experiences and the annihilation energy power are calculated. It is found that the total energy of QIAS and the energy resulting from hydrogen-antihydrogen annihilation are important step towards the establishment of a cold fusion power station.

A mechanism for spin electron acoustic soliton observed in a spin-polarized nanosized electron-hole plasma

The formation and the characteristics of spin electron acoustic (SEA) soliton in a beam interacting spin-polarized electron-hole plasma are investigated. These wavepackets are supposed to be the source of heating during the excitation process. We have used the separate spin evolution-quantum hydrodynamic (SSE-QHD) model along with Maxwell equations and derived the Korteweg–de Vries (KdV) equation by using the reductive perturbation method (RPM). We note that the larger values of beam density and spin polarization can change the soliton nature from rarefactive to compressive. Our findings may be important to understand the characteristics of localized spin-dependent nonlinear waves in nanosized semiconductor devices.

Electrostatic Solitary Structures in Space Plasmas: Soliton Perspective

Occurrence of electrostatic solitary waves (ESWs) is ubiquitous in space plasmas, e.g., solar wind, Lunar wake and the planetary magnetospheres. Several theoretical models have been proposed to interpret the observed characteristics of the ESWs. These models can broadly be put into two main categories, namely, Bernstein–Green–Kruskal (BGK) modes/phase space holes models, and ion- and electron- acoustic solitons models. There has been a tendency in the space community to favor the models based on BGK modes/phase space holes. Only recently, the potential of soliton models to explain the characteristics of ESWs is being realized. The idea of this review is to present current understanding of the ion- and electron-acoustic solitons and double layers models in multi-component space plasmas. In these models, all the plasma species are considered fluids except the energetic electron component, which is governed by either a kappa distribution or a Maxwellian distribution. Further, these models consider the nonlinear electrostatic waves propagating parallel to the ambient magnetic field. The relationship between the space observations of ESWs and theoretical models is highlighted. Some specific applications of ion- and electron-acoustic solitons/double layers will be discussed by comparing the theoretical predictions with the observations of ESWs in space plasmas. It is shown that the ion- and electron-acoustic solitons/double layers models provide a plausible interpretation for the ESWs observed in space plasmas.

Obliquely overtaking collisions of electrostatic N-soliton in the Thomas-Fermi dense magnetoplasma

Overtaking collision of unidirectional dust acoustic waves in the Thomas-Fermi dense magnetoplasma has been investigated. The system consists of classical negatively charged dust particles with degenerate electrons and ions. Nonlinear Korteweg-de Vries (KdV) equation that characterizing the dust acoustic solitons in such a plasma model is derived. The system admits only rarefactive solitary waves. Hirota's bilinear method is used to investigate the overtaking collision of two and three-soliton solutions. The exchange of energies due to the overtaking collisions is affected by physical parameters such as the electron equilibrium density, the dust temperature, and the obliquity angle. This causes the solitons behavior to be alternated. The amplitude, and width increase as the dust temperature and electron density decrease or when the dust density increases. The magnetic field affects only the soliton's width. The phase shifts are also affected by the system parameters. The current study is an attempt to illuminate the properties of N-soliton in Thomas-Fermi dense magnetoplasma that are applicable in compact astrophysical objects such as white dwarfs and high-intensity laser-solid matter interaction experiments.

Low‐frequency variable charge solitary waves in a collisionless dusty plasma with a Cairns‐Gurevich ion velocity distribution

AbstractIn this paper, the problem of large amplitude dust acoustic (DA) solitons has been addressed in a charge varying dusty plasma with ions following a Cairns‐Gurevich distribution. Based on the orbit motion limited approach, the correct Cairns‐Gurevich ion charging current is presented for the first time. The expression relating the variable dust charge to the plasma potential is given in terms of the Lambert function and we take advantage of this transcendental function to, carefully, analyse DA solitons in a charge varying dusty plasma with trapped nonthermal ions. Our results show that the spatial patterns of the variable charge solitary wave are significantly changed due to the presence of ion population modelled by the Cairns‐Gurevich distribution. An addition of a small concentration of trapped nonthermal ions makes the solitary structure less spiky, grows the net negative charge residing on the dust grain surface, and contributes to the electron depletion. Finally, our investigation is extended to highlight the effect of the grain dust charge variation. We have shown that under certain conditions, the impact of dust charge fluctuation may furnish an alternate physical mechanism rasing anomalous dissipation, which becomes more strong and may predominate over the dispersion as the nonthermal character of ions following the Cairns‐Gurevich distribution increases.

Elastic and inelastic particles scattering by dust acoustic soliton. A new oscillatory process in dusty plasma

The parameters of scattering (reflection) of charged particles by the leading edge of a dust acoustic soliton are analyzed. The soliton profile is calculated using the Sagdeev pseudopotential approach. To analyze the motion of charged particles, the Newton’s second law is used. It is shown theoretically that the charged particle scattering can be elastic and inelastic. The nature of scattering significantly depends on the presence of dissipation. In the dissipative case, charged particles scattering is the process of an oscillatory nature. It is shown that it can be considered as a new type of oscillations of charged particles in plasma. The parameters of the oscillations are calculated both numerically (nonlinear case) and analytically (within the linear approximation). Theoretical results are compared with known experimental results, as well as the applied aspect is stated.

Quantum Electron Acoustic Solitons and Double Layers with κ-deformed Kaniadakis Distributed Electrons

The present investigation is dedicated to the study of propagation characteristics of electron acoustic (EA) waves and double layers in the quantum plasma system containing inertialess hot electrons and inertial cold electrons with stationary ions forming the charge neutralizing background. It is assumed that hot electrons follow κ-deformed Kaniadakis distribution as governed by the parameter κ. Using the appropriate stretched coordinates and reductive perturbation method (RPM) the Korteweg-de Vries (KdV) and modified KdV (mKdV) equations have been derived. For the sake of analysis, a limit of range of deformation parameter (κ) has been set as -0.4≤κ≤0.4. For the defined range, it has been observed that plasma system supports rarefactive solitary structures. The amplitude and width of KdV soliton have been significantly affected by the quantum effects and remains unaffected by the deformation parameter (κ). The analysis was further extended to the derivation of mKdV equation to investigate the existence of small amplitude double layers (DLs). Only negative potential DLs are found to exist whose dynamics significantly depends on deformation parameter (κ), quantum effects (H) and hot to cold electron density ratio (α). The outcome of the present discourse may be helpful to understand the use of generalized entropies in the environment of plasma physics.

Dust Acoustic Solitons in the Plasma of the Dusty Exosphere of the Moon

Dust Acoustic Solitons in the Plasma of the Dusty Exosphere of the Moon

Large-amplitude dust acoustic solitons in an opposite polarity dusty plasma with generalized polarization force

Linear and nonlinear dust acoustic (DA) waves have been investigated in an opposite polarity dusty plasma comprisingnegatively and positively charged dust grains, Maxwellian electrons and ions, including the generalized polarization force effect. The properties of linear DA waves have been significantly altered by the dual dust polarity and polarization force. Large amplitude DA solitons have been discussed in the framework of the Sagdeev potential technique. Our results show that both rarefactive and compressive solitons can exist in such a dusty plasma. The basic features of the Sagdeev potential have been examined under the effect of the polarization force parameter R, the ratio of the charge number of the positive dust to that of the negative dust Z, and the Mach number M. The results show that these parameters play a significant role in determining the region of existence of large amplitude DA solitons.