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The multicomponent quantum hydrodynamic model of collisional, unmagnetized electron-ion-dust quantum plasma has been considered to derive the nonlinear damped modified Gardner equations. For compositional values close to the critical composition, damped modified Gardner equations are formulated using an expanded version of the reductive perturbation technique. It is found that this electron-ion-dust quantum plasma provides the required critical composition. It is possible to construct a new approximate analytical solitary wave solution, which appears to have novel nonlinear properties incorporated in it. Through a recently found approximate analytical solution, the impact of dust ion and quantum diffraction parameter collision on solitary wave structures is investigated. It can be seen that the structures of solitary wave solutions are distinctively modified by dust ion collision and the quantum diffraction parameter. The crucial role of collision parameter and the quantum diffraction parameter on the solitary wave structures has been studied extensively. [ABSTRACT FROM AUTHOR]

In this paper, the propagation of pulse wave in a deformable elastic vessel filled with inviscid blood is studied. Starting from the stress–strain relationship of blood vessel wall, momentum conservation equation and the Naiver–Stokes equation, the basic equations describing the wall motion and blood flow are established. By utilizing reductive perturbation technique and long wave approximation theory, the basic equations are simplified into a classical third-order mKdV equation with variable coefficients. In order to describe the propagation characteristics of pulse wave more accurately, a fifth-order variable-coefficient mKdV equation is derived. Then, the tanh-function method is applied to find the localized traveling wave solutions of these equations. Based on these localized traveling wave solutions, we further investigate the effects of higher order terms and initial vessel deformation on the characteristics of pulse wave propagation, blood flow velocity and the volume of blood flow. The results show that the higher-order nonlinear and dispersion terms lead to the distortion of the wave, while the initial deformation of the tube wall will influence the wave amplitude and wave width. [ABSTRACT FROM AUTHOR]

Dynamics of nonlinear ion-acoustic waves (IAWs) are studied for Venus' lower atmosphere at an altitude of 200 − 1000 km. Two-soliton, nonlinear solitary and periodic waves in a three-component plasma consisting of H + and O + ions with kappa distributed electrons are studied. Using the reductive perturbation technique (RPT), the Korteweg-de Vries (KdV) equation is derived and a Planar dynamical system is formed for the KdV equation using a travelling wave transformation. A phase portrait is drawn to analyze nonlinear wave behaviors by adjusting the parameters κ (spectral index), γ (unperturbed number density ratio), and V (travelling wave speed). Increasing values of κ amplify amplitudes for solitary and periodic waves, narrow down the width of the solitary wave, and broaden the width of the periodic wave. Increasing value of γ boosts amplitude of the solitary wave with unchanged width, while amplitude of the nonlinear periodic wave decreases and width widens. Increasing value of V enhances amplitudes and reduces widths for both solitary and periodic waves. Two-soliton solutions for the KdV equation are studied using the Hirota direct method. Increasing value of γ reduces amplitude of the soliton without affecting the width and increasing value of κ reduces width of the soliton. Phase shift for two-soliton is also shown and found that for different values of κ , the phase shift increases on increasing value of γ . The findings of our result aid in understanding the dynamics of nonlinear waves and two-soliton solutions in Venus' lower ionosphere. [ABSTRACT FROM AUTHOR]

In this article, the nonlinear plasma model known the damped modified Korteweg–de Vries equation under consideration on the base of analytical technique to know the novel behavior of this nonlinear model. We formulated the nonlinear plasma model by utilizing the RP (reductive perturbation) technique with basic set of fluid system which consisted on cold negative charge dust fluid, immobile background neutral charges, positive charge ion fluid, fast (ionized) electrons and thermally electrons. We also constructed various kinds of novel soliton solutions including kink wave solitons, periodic solitary waves, anti-kink wave solitons for the damped modified KdV equation. The determined soliton solutions are novel, interested and did not determined in the previous research. The physical interpretation of demonstrated solutions represent in contour, two-dim and three-dim with computational software. The study prove that our proposed approach is powerful, efficient and can also be fruitful for study of other nonlinear models.

A theoretical investigation is done in this multicomponent dusty plasma with non-thermal ions, relativistic electrons and mobile dusts through reductive perturbation technique by deriving Korteweg–de Vries (KdV) equation. Role of ions, dusts and relativistic electrons streamings are investigated in this multicomponent plasma to form compressive and rarefactive KdV solitons. Interestingly, for some pairs of streamings of ions, dusts and relativistic electrons, only compressive solitons are seen to produce whereas for some other pairs rarefactive KdV solitons with some interesting characteristics are seen to produce. In this theoretical investigation, mobile dust particles play a very crucial role in the formation of compressive and rarefactive KdV solitons. Application of this multicomponent plasma model in astrophysical and space plasma is briefly discussed. [ABSTRACT FROM AUTHOR]

Nonplanar two-dimensional (2D) spherical dust acoustic solitary waves (DASWs) in unmagnetized, collisionless, Boltzmann distributed electrons, negatively charged dust fluid and trapped ions following vortex-like ion distribution, in a dusty plasma were investigated theoretically. Using standard reductive perturbation technique, which is valid for a small but finite amplitude limit condition, nonlinear spherical modified Korteweg–de Vries (K-dV) equation was achieved. Two motions are observed in the radial and angular directions, with transverse perturbations in the angular direction. It is found that the properties of the DASWs in a 2D spherical geometry differ from 1D spherical geometry where transverse perturbations and unidirectional waves are observed for 2D spherical geometry. The effects of dusty plasma parameters and vortex-like ion distribution on the properties (such as amplitude and width) of spherical DASWs were theoretically investigated. These numerical investigations show that under such specific conditions, only compressive DASWs can exist. [ABSTRACT FROM AUTHOR]

The impact of an external periodic force on the characteristics of dust ion-acoustic solitary waves in a superthermal magnetised plasma is investigated. To obtain the forced Zakharov–Kuznetsov (FZK) equation from fundamental governing equations, the well-known reductive perturbation technique is used. Furthermore, the ZK equation is transformed into planar dynamical systems to analyse the phase portrait of the system. Based on the approximated analytical solution of the FZK equation, it is observed that both positive potential compressive and negative potential rarefactive solitons exist in this model. The amplitudes of positive potential solitons are found to increase along with the increase in external periodic force, whereas the amplitudes of negative potential solitons are found to decrease. It is observed that due to the presence of external forced potential, the amplitude of solitons naturally takes on a variety of peak forms, whereas in the absence of this external force, the phenomenon of variety in peak formation does not happen. The results of this present investigation are interesting and may be helpful in understanding nonlinear phenomena in space and astrophysical plasma, such as the ionosphere, terrestrial plasma sheet, mesosphere and lower thermosphere. [ABSTRACT FROM AUTHOR]

The non-linear propagation of dust acoustic wave (DAW) in collisionless, unmagnetized, viscous dusty plasma containing electrons with Maxwell-Boltzmann distribution, two-temperature ions, and highly negatively charged dust grains, are investigated through the fabric of the Kadomtsev-Petviashvili-Burgers (KPb) equation. Following the approach of the reductive perturbation technique (RPT), the KPb equation is constructed from the governing equation, and further, utilizing traveling wave transformation, the KPb equation is converted into an ordinary differential equation (ODE). Analyzing phase portraits for the KPb system varying different plasma parameters, it is found that the KPb system includes shock, solitary as well as periodic solutions. But, in case of lack of Burgers term, the system only provides the solitary and periodic solutions which are directly generated from the KP equation, and further, a shock solution of the KPb equation is derived by applying the (G ′ / G) -expansion method. Introducing the indirect F-function method and incorporating a Jacobi elliptic function, a finite-amplitude periodic solution for the KPb equation is also constructed. Finally, the impacts of the physical parameters on wave propagation in the present system are illustrated from a numerical standpoint. [ABSTRACT FROM AUTHOR]

The time‐fractional Gardner Burger (TFGB) equation is an efficient tool for studying nonlinear fluctuations of different types of the wave profiles, such as the gravity solitary waves in the ocean and the dust ion acoustic wave (DIAW) in a plasma environment. Here, to create an example for the existence of the classical Gardner Burger (GB) equation, a multicomponent plasma environment is considered and a classical GB equation has been derived using the basic governing equation by employing reductive perturbation technique (RPT). In addition, employing Agrawal's technique, the classical GB equation is transformed to the TFGB equation by applying the Riesz fractional derivative to the time‐fractional term. To solve TFGB equations, a new approach, utilizing the improved Bernoulli subequation function method (IBSEFM), is adopted. The physical structures of the solution are explored through some two‐ and three‐dimensional figures, and the significant impact of Burgers term and fractional order of the TFGB equation are demonstrated numerically. Finally, the wave dynamics of the DIAW in the parametric space for the present plasma environment are described from the numerical understanding. [ABSTRACT FROM AUTHOR]

The nonlinear propagation of dust acoustic solitary waves (DASWs) in an unmagnetized dusty plasma consisting of negatively charged dust fluid, Boltzmann distributed electrons with two different temperatures, Boltzmann distributed ions with two distinct temperatures are investigated. By employing the reductive perturbation technique that is valid for a small but finite amplitude limit, the Korteweg–de Vries (KdV) equation, have been derived. Our results reveal that the main quantities of DASWs (such as amplitude and width) are affected by electrons with two different temperatures (as well as ions), temperature ratios, and the number densities of two species of ions. It is shown that both positive and negative potential DASWs occur in this case. [ABSTRACT FROM AUTHOR]

The characteristic of ion-acoustic solitary and shock waves propagating in a non-extensive plasma is analysed using the framework of the modified Korteweg–de Vries–Burgers (MKdVB) equation. Employing reductive perturbation technique (RPT), the MKdVB equation is derived from the basic guiding equations and further, the equation is converted to a dynamic system using travelling wave transformation. Varying different plasma parameters, phase portraits for the MKdV system are drawn and using bifurcation theory of planar dynamical system, it is observed that the MKdV system may contain shock, solitary and periodic solutions. However, it is evident from the phase portrait analysis of the MKdVB equation that due to the impact of Burgers term, the system includes only the shock and solitary solutions. Initially, different patterned solutions of the MKdV equation are directly derived from the corresponding Hamiltonian of the system, and employing the weighted residual method (WRM), the approximate analytical solutions of the MKdVB equation are explored using the solution of MKdV equation as initial solution. These solutions come as a desired pattern that was predicted by the phase portraits. Finally, some graphs are depicted from a numerical standpoint by which the effects of physical parameters on wave propagation are well understood. [ABSTRACT FROM AUTHOR]

Nonlinear propagation of magnetoacoustic waves in magnetized, collisionless, warm bi-ion plasmas with positive and negative ions of different masses and charge states are investigated. The two-fluid model is used here. Using reductive perturbation technique, the Korteweg-de Vries equation is derived as nonlinear dispersion relation, and its solution for the magnetoacoustic solitons propagating in the direction perpendicular to the external magnetic field is obtained. Using experimental values for the plasma parameters, magnetoacoustic soliton structures for K-fullerene plasma are illustrated along with some other useful alkali-fullerene plasmas. [ABSTRACT FROM AUTHOR]

The influence of the dust–ion collision effect on the propagation of ion–acoustic waves (IAWs) in a collisional magnetized dusty plasma containing positive ions, dust grains with a negative charge and the electrons that follow combined Kappa–Cairns distribution is observed. Employing reductive perturbation technique (RPT), the damped Kadomtsev–Petviashvili (DKP) equation is derived from the basic governing equations and it is observed that there are some critical points for the plasma parameters for which the amplitude of solitary solution of DKP equation diverges. Then modified damped Kadomtsev–Petviashvili (MDKP) equation is derived by stretching the dependent variables in a different manner and the finite-amplitude soliton is explored there. The influence of various plasma parameters viz. entropic index (κ), nonthermal parameter (), dust–ion collisional frequency (), ratio of normalized electron density to ion density (μ), etc. on wave propagation is investigated numerically. Finally, comparative studies are drawn between the solitary wave solutions for different models. [ABSTRACT FROM AUTHOR]

The study of heavy nucleus acoustic (HNA) periodic and solitary waves in degenerate relativistic magneto-rotating quantum plasma (DRMQP) composed of relativistic degenerate electrons, light nuclei and non-degenerate mobile heavy nuclei is presented. Reductive perturbation technique is adopted to derive the Korteweg–de Vries (KdV) type equation for studying the characteristics of HNA periodic waves. Further energy balance equation is derived by using Sagdeev potential approach and HNA cnoidal wave solution is determined. Only positive potential nonlinear periodic and solitary structures are observed. The impact of number density ratio, charge density, magnetic field strength and rotational effect is analyzed on the characteristics of HNA cnoidal and solitary waves. The results of this investigation may shed light on the salient features of different nonlinear HNA waves in different astrophysical environments, especially in white dwarfs. [ABSTRACT FROM AUTHOR]

An investigation of nonlinear dust-acoustic cnoidal waves in a magnetized quantum dusty plasma consisting of inertial dust, inertialess electrons and ions is presented. The Korteweg–de Vries (KdV) equation is obtained by employing reductive perturbation technique and analytical solution of KdV equation is derived by employing the Sagdeev pseudopotential approach. Numerical analysis of the solution is performed to study the characteristics of the dust-acoustic cnoidal waves. In this study, positive (negative) potential dust-acoustic cnoidal waves are observed for the case of positive (negative) dust grains. The influence of various parameters such as quantum diffraction parameter of electrons and ions, magnetic field strength, obliqueness, concentration of ions and Fermi temperature (electrons and ions) has been studied. In the limiting case, dust-acoustic cnoidal wave solution is found to reduce to solitary wave solution. [ABSTRACT FROM AUTHOR]

The nonlinear propagation of ion-acoustic (IA) solitons and double layers (DLs) in a nonrelativistic degenerate plasma is investigated. This plasma model consists of negative ions, positive ions, and degenerate electrons. The Gardner equation is derived using the reductive perturbation technique. Both the Gardner solitons and DLs exist in our model. The characteristics of these waves are analyzed. It is found that the properties of these structures depend on the densities, the temperature, and the mass ratio of the ions and also on the chemical potential of the degenerate electrons. Additionally, it is found that the system sustains two different IA modes with different phase velocities known as slow and fast IA modes. These investigations can be useful in space plasma situations that contain opposite polarity ions such as compact astrophysical objects like white dwarfs. [ABSTRACT FROM AUTHOR]

The characteristics of obliquely propagating dust acoustic solitary wave in magnetized dusty plasma are analysed by considering the plasma to have electrons, two-temperature ions and massive dust grains with heavy charge. The reductive perturbation technique is used to derive relevant Korteweg-deVries (KdV) equation. The effect of density and temperature of hot and cold ions, angle of wave propagation, and mass, charge and temperature of the dust grains on the soliton characteristic is investigated in greater detail. The situation of electron-depleted plasma is also uncovered.

The higher-order, low-amplitude inertial Alfvén wave (IAW) dressed soliton and chaos are investigated in a magnetized plasma. In the linear limit, the dispersion relation for propagation of IAWs in plasmas is also obtained in the presence of electron thermal effects and illustrated numerically. It is found that the electron inertial length plays an important role for wave dispersion effects and its phase speed is increased on including the electron temperature in the model. The reductive perturbation method is employed to obtain the first-order IAW Korteweg-de Vries (KdV) soliton and second-order dressed soliton solutions analytically, which gives electron density dip (or rarefactive) structure and moves with super Alfvénic speed in plasmas. The numerical illustrations of the KdV and dressed IAW solitons are also presented by using the laboratory and space plasma parameters given in the literature. Furthermore, a numerical study of quasi-periodicity and chaotic behaviour of IAWs in the presence of external periodic force is also discussed in detail. The effects of plasma beta (which depends on plasma density, electron temperature, and magnetic field intensity) and obliqueness of the wave propagation on the formation of nonlinear Alfvénic wave structures have also been presented. [ABSTRACT FROM AUTHOR]

The characteristics of ion-acoustic solitary waves in rotating, weakly relativistic, magnetised and collisionless plasma system comprising electron, positron and ion (EPI) under a periodic external force, whose constituents electron and positron obey Boltzmann distribution, are investigated by deriving forced Zakharov–Kuznetsov (FZK) equation. FZK equation is constructed using reductive perturbation technique (RPT) which is based on multiple-scale analysis of dependent variables. The effects of physical parameters such as the ratio of temperature of electron and positron, the strength of external periodic force, positron concentration in electron background, ion temperature and magnetic field on the analytical solitary wave solution of FZK equation are observed. It is seen that the behaviours of ion-acoustic wave are significantly affected due to the presence of positron and the periodic external forces. The results of this work may be applied when the above-mentioned plasma environment is found in laboratory as well as in space. [ABSTRACT FROM AUTHOR]

The electron-acoustic solitons are studied with two temperature electrons (a hot trapped having vortex-like velocity distribution and a warm adiabatic fluid) and stationary ions. The theoretical model is based on the observations of a mixture of the hot, tenuous magnetospheric and warm, dense magnetosheath plasma particles associated with the asymmetric magnetic reconnection at the Earth’s magnetopause by Magnetospheric Multiscale (MMS). Using the reductive perturbation technique, the model supports the existence of nonlinear electron-acoustic structures derived from the mKdV-like equation. The electron-acoustic waves propagate at supersonic speeds above the electron sound speed. The results are applied to observations of electric field structures in the electron diffusion region (EDR).

In this article, using the standard reductive perturbation technique (RPT) to the basic governing equations for plasma comprising stationary ions, cold electrons and hot electrons abiding by vortex-like distribution, nonplanar Schamel Burger (NSB) equations is derived. In order to study the propagating properties of Electron acoustic (EA), progressive wave solution is obtained by employing the weighted residual method (WRM). Most of the observations of the EA wave are limited to the plasma environment where the effects of viscosity, collisions, ion streaming velocity are totally neglected. In our present observation, propagation of EA waves in a viscous plasma is described considering a weak damping (by adding a Burgers term) due to the inner particle collision and viscosity. Special attention has been given to study the impact of the other physical parameters in wave propagation in the framework of the Schamel Burgers medium. [ABSTRACT FROM AUTHOR]

The propagation of magnetoacoustic (fast magnetohydrodynamic) waves in pair-ion (PI) fullerene plasma is studied in the linear and nonlinear regimes. The pair-ion (PI) fullerene plasma is theorized as homogeneous, magnetized, warm and collisionless. Employing multi-fluid magnetohydrodynamic model, the dispersion relation is obtained and wave dispersion effects which appear through ion inertial length are discussed. Using reductive perturbation technique (RPT), the Korteweg–de Vries (KdV) equation is derived and its solution for small but finite amplitude magnetoacoustic solitons propagating in the direction perpendicular to the external magnetic field is presented. The compressive magnetoacoustic soliton (i.e. positive potential pulse) propagating with super Alfvénic speed is obtained in magnetized PI fullerene plasma. The variations in the amplitude and width of the magnetoacoustic soliton structures are also illustrated by using numerical values of the plasma parameters such as ions' density, temperature difference between fullerene ions and magnetic field intensity, which have been taken from the PI plasma experiments already published in the literature. [ABSTRACT FROM AUTHOR]

In this article, the nonlinear plasma model known the damped modified Korteweg–de Vries equation under consideration on the base of analytical technique to know the novel behavior of this nonlinear model. We formulated the nonlinear plasma model by utilizing the RP (reductive perturbation) technique with basic set of fluid system which consisted on cold negative charge dust fluid, immobile background neutral charges, positive charge ion fluid, fast (ionized) electrons and thermally electrons. We also constructed various kinds of novel soliton solutions including kink wave solitons, periodic solitary waves, anti-kink wave solitons for the damped modified KdV equation. The determined soliton solutions are novel, interested and did not determined in the previous research. The physical interpretation of demonstrated solutions represent in contour, two-dim and three-dim with computational software. The study prove that our proposed approach is powerful, efficient and can also be fruitful for study of other nonlinear models. • The dynamic characteristics of the dusty plasma. • Nonlinear behavior of dust acoustic periodic soliton structures. • The qualitative analysis, bifurcation and computational methods are applied. [ABSTRACT FROM AUTHOR]

The characteristics of obliquely propagating dust acoustic solitary wave in magnetized dusty plasma are analysed by considering the plasma to have electrons, two-temperature ions and massive dust grains with heavy charge. The reductive perturbation technique is used to derive relevant Korteweg-deVries (KdV) equation. The effect of density and temperature of hot and cold ions, angle of wave propagation, and mass, charge and temperature of the dust grains on the soliton characteristic is investigated in greater detail. The situation of electron-depleted plasma is also uncovered. [ABSTRACT FROM AUTHOR]

Analytical solitary wave solution of the dust ion acoustic waves (DIAWs) is studied in the framework of the damped Korteweg–de Vries–Burgers (DKdVB) equation in an unmagnetised collisional dusty plasma consisting of negatively charged dust grain, positively charged ions, q-nonextensive electrons, and neutral particles. Using Reductive Perturbation Technique, the DKdVB equation is obtained for DIAWs. The effects of different physical parameters such as dust ion collision frequency parameter ( ν i d 0 \({\nu_{id0}}\)), viscosity coefficient (η10), the entropic index (q), the speed of the travelling wave (M0), and the ratio between the unperturbed densities of the electrons and ions (μ) on the analytical solution of DIAWs are observed. The results of the present article may have applications in laboratory and space plasmas. [ABSTRACT FROM AUTHOR]

Using a reductive perturbation technique (RPT), the Korteweg‐de Vries (KdV) equation for nonlinear electrostatic waves in multi‐ion plasmas is derived with appropriate boundary conditions. Furthermore, compressive and rarefactive cnoidal wave and soliton solutions are discussed. In our model, the multi‐ion plasma consists of light dynamic warm ions, heavy cold ions, and inertialess electrons, which follows the Maxwell‐Boltzmann distribution. It is observed that in such an unmagnetized multi‐ion plasma, two characteristic electrostatic waves i.e., slow ion‐acoustic (SIA) waves and fast ion‐acoustic (FIA) waves, can propagate. The results are discussed by considering two types of multi‐ion plasmas i.e., H+–O+–e plasma and H−–O+–e plasma that exist in space plasmas. It is found that for H+–O+–e plasma, the SIA cnoidal wave and soliton form both positive (compressive) and negative (rarefactive) potential pulses, which depend on the temperature and density of the light and warm ions. However, only electrostatic positive potential structures are obtained for FIA cnoidal wave and soliton in H+–O+–e plasma. In the case of H−–O+–e plasma, the SIA cnoidal wave and soliton form only compressive structures, while the FIA cnoidal wave and soliton compose rarefactive structures. The effects of light ions' density and temperature on nonlinear potential structures are investigated in detail. The parametric results are also demonstrated, which are applicable to space and laboratory multi‐ion plasma situations. [ABSTRACT FROM AUTHOR]

The nonlinear propagation of dust acoustic waves with dust charge fluctuation in presence of superthermal (kappa) electrons and ions has been investigated. Reductive perturbation technique along with space-time stretched coordinates is used to transform the basic nonlinear partial differential equations to a modified Korteweg-de-Vries equation. The modified Korteweg-de-Vries equation governs the dynamics of the small amplitude solitary waves in a superthermal dusty plasma. It is observed that the presence of kappa distributed electrons and ions significantly change the amplitude of solitons in an inhomogeneous environment. The present investigations may be useful to understand the nonlinear propagation of dust acoustic solitary waves in laboratory and space plasma. [ABSTRACT FROM AUTHOR]

In this study, nonlinear wave modulation in nanorods is examined on the basis of nonlocal elasticity theory. Eringen's nonlocal elasticity theory is employed to derive nonlinear equations for the motion of nanorods. The analysis of the modulation of axial waves in nonlocal elastic media is performed, and the reductive perturbation method is used for the solution of the nonlinear equations. The propagation of weakly nonlinear and strongly dispersive waves is investigated, and the nonlinear Schrödinger (NLS) equation is acquired as an evolution equation. For the purpose of a numerical investigation of the nonlocal impacts on the NLS equation, it has been investigated whether envelope solitary wave solutions exist by utilizing the physical and geometric features of the carbon nanotubes. Amplitude dependent wave frequencies, phase and group velocities have been obtained and they have compared for the linear local, the linear nonlocal, the nonlinear local and the nonlinear nonlocal cases. [ABSTRACT FROM AUTHOR]

This article investigates the field-driven motion of curved domain walls in ferromagnetic nanostructures under the framework of modified Landau–Lifshitz–Gilbert equation with inertial effects. The considered governing equation involves the torques arising from nonlinear dissipative (viscous and dry friction) and inertial effects. We study the most relevant dynamical features in the steady dynamical regime for the considered model by employing the reductive perturbation technique. Finally, we illustrate the results numerically for the various domain wall surfaces (plane, cylinder, and sphere) and discuss their physical significance. The results obtained here agree with the recent theoretical and experimental observations. • Dynamics of curved domain walls in ferromagnetic nanostructures is investigated. • An analytical expression of the zeroth-order magnetization vector has been derived. • A partial differential equation of domain wall velocity has been obtained. • Breakdown value of the velocity does not depend on nonlinear viscous dissipation. • Inertial and nonlinear damping effects decrease the velocity as time evolves. [ABSTRACT FROM AUTHOR]

In this report, a detailed investigation on the study of dust acoustics solitary waves solution with negatively dust charge fluctuation in dusty plasma corresponding to lower and higher temperature nonthermal ions with trapped electrons is presented. We consider temporal variation of dust charge as a source of dissipation term to derive the lower order modified Kadomtsev-Petviashvili equation by using the reductive perturbation technique. Solitary wave solution is obtained with the help of sech method in presence of trapped electrons and low (and high) temperature nonthermal ions. Both nonthermality of ions and trapped state of the electrons are found to have an imperative control on the nonlinear coefficient, dissipative coefficient as well as height of the wave potential. [ABSTRACT FROM AUTHOR]

Bifurcations of nonlinear electron acoustic solitary waves and periodic waves in an unmagnetized quantum plasma with cold and hot electrons and ions has been investigated. The one dimensional quantum hydrodynamic model is used to study electron acoustic waves (EAWs) in quantum plasma. Applying the well known reductive perturbation technique (RPT), we have derived a Korteweg-de Vries (KdV) equation for EAWs in an unmagnetized quantum plasma. By using the bifurcation theory and methods of planar dynamical systems to this KdV equation, we have presented the existence of two types of traveling wave solutions which are solitary wave solutions and periodic traveling wave solutions. Under different parametric conditions, some exact explicit solutions of the above waves are obtained. [ABSTRACT FROM AUTHOR]

Abstract: The propagation of nonlinear ion-acoustic waves in magnetized plasma consisting of cold ions, hot electrons and positrons has been studied. It is demonstrated that in the case of weak nonlinearity the ion-acoustic waves are described by the Korteweg–de Vries (K-dV) equation. The influence of finite positron density and temperature and external magnetic field on the properties of soliton-like waves is discussed. [Copyright &y& Elsevier]

• DW velocity exhibits a jump at the threshold in the presence of current-driven motion. • The threshold value of the external stimulus remains independent of the non-linear viscous damping coefficient. • Walker-breakdown velocity is field-independent and current-dependent for the metallic and semiconductor FMs. • The Rashba field significantly influences the DW motion and results in the enlargement of the steady-state dynamic regime. • Observed larger sensitivity of the Walker breakdown field/current for the semiconductor FMs compared to the metallic ones. This work reveals an analytical investigation of the curved domain wall motion in ferromagnetic nanostructures in the framework of the extended Landau-Lifshitz-Gilbert equation. To be precise, the study delineates the description of curved domain wall motion in the steady-state dynamic regime for metallic and semiconductor ferromagnets. The study is done under the simultaneous action of the Rashba field and nonlinear dissipative effects described via the viscous-dry friction mechanism. By means of reductive perturbation technique and realistic assumption on the considered parameters, we establish an analytical expression of the steady domain wall velocity that depends on mean curvature of domain wall surfaces, nonlinear dissipation coefficients, Rashba parameter, external magnetic field, and spin-polarized electric current. In particular, it is observed that the domain wall velocity, mobility, threshold, and Walker breakdown can be manipulated by the combined mechanism of the Rashba field and nonlinear dissipation coefficients. Finally, the obtained analytical results are illustrated numerically for the curved domain walls through constant-curvature surfaces under-considered scenarios. The results presented herein are in qualitatively good agreement with the recent observations. [ABSTRACT FROM AUTHOR]

The electron-acoustic solitons are studied with two temperature electrons (a hot trapped having vortex-like velocity distribution and a warm adiabatic fluid) and stationary ions. The theoretical model is based on the observations of a mixture of the hot, tenuous magnetospheric and warm, dense magnetosheath plasma particles associated with the asymmetric magnetic reconnection at the Earth's magnetopause by Magnetospheric Multiscale (MMS). Using the reductive perturbation technique, the model supports the existence of nonlinear electron-acoustic structures derived from the mKdV-like equation. The electron-acoustic waves propagate at supersonic speeds above the electron sound speed. The results are applied to observations of electric field structures in the electron diffusion region (EDR). [ABSTRACT FROM AUTHOR]