Dust Ion Acoustic Solitons Research Articles

Nonlinear dust–ion acoustic waves in a dusty plasma with non-extensive electrons and ions

AbstractUsing the reductive perturbation approach, dust–ion acoustic solitons and double layers (DLs) have been studied in a dust–electron–positron–ion (d-e-p-i) plasma composed of q-distributed electrons and positrons, warm fluid ions, and a fraction of immobile dust grains. Existence domains of either solitary waves or DLs are presented and their parametric dependence determined. It is found that particle non-extensivity, dust concentration and positron concentration may drastically affect these existence domains and may play a key role in defining the polarity of these localized structures. Our results should assist in interpreting the nonlinear structures that may occur in astrophysical environments.

Arbitrary amplitude dust ion acoustic solitary waves in a magnetized suprathermal dusty plasma

The linear and nonlinear dust-ion-acoustic (DIA) wave propagating obliquely with respect to an external magnetic field is studied in a magnetized complex plasma which consists of a cold ion fluid, superthermal electrons, and static dust particles. The propagation properties of two possible modes (in the linear regime) are investigated. It is found that the electron suprathermality and the electron population decrease the phase velocities of both modes, while obliqueness leads to increase of separation between two modes. An energy-like equation derived to describe the nonlinear evolution of DIA solitary waves. The influences of electron suprathermality, obliqueness, and electron population on the existence domain of solitary waves and the soliton characteristics are examined. It is shown that the existence domain of the DIA soliton and its profile are significantly depending on the deviation of electrons from thermodynamic equilibrium, electrons population, and obliqueness. It is also found that the suprathermal plasma supports the DIA solitons with larger amplitude.

Dust-ion-acoustic Gardner solitons in a dusty plasma with bi-Maxwellian electrons

The nonlinear propagation of dust-ion-acoustic (DIA) waves in a dusty plasma with bi-Maxwellian electrons, namely, lower and higher temperature electrons (composed of negatively charged stationary dust, inertial ions, and non-inertial two-temperature-electrons) is investigated by deriving the Gardner equation using the reductive perturbation technique. The basic features (amplitude, width, etc.) of the hump (positive potential) and dip (negative potential) shaped DIA solitons (Gardner solitons, i.e., GSs) are found to exist beyond the Korteweg-de Vries (K-dV) limit. These DIA-GSs are qualitatively different from the K-dV and modified K-dV solitons. It is also shown that depending on the parameter σ (where σ=Te1/Te2, Te1 and Te2 being the temperatures of two distinct electrons and Te1≪Te2), the DIA-GSs exhibit hump and dip shape solitary structures. The implications of our results in understanding the localized nonlinear electrostatic perturbations observed in double-plasma machines, rf discharge plasma, noctilucent cloud region in Earths atmosphere, etc., where population of two thermal electrons can significantly dominate the wave dynamics, are also briefly addressed.

Ion-acoustic solitons in dusty plasma

The dynamics of dust ion-acoustic solitons is analyzed in a wide range of dusty plasma parameters. The cases of both a positive dust grain charge arising due to the photoelectric effect caused by intense electromagnetic radiation and a negative grain charge established in the absence of electromagnetic radiation are considered. The ranges of plasma parameters and Mach numbers in which “conservative” (nondissipative) solitons can exist are determined. It is shown that, in dusty plasma with negatively charged dust grains, both compression and rarefaction solitons can propagate, whereas in plasma with positively charged dust grains, only compression solitons can exist. The evolution of soliton-like compression and rarefaction perturbations is studied by numerically solving the hydrodynamic equations for ions and dust grains, as well as the equation for dust grain charging. The main dissipation mechanisms, such as grain charging, ion absorption by dust grains, momentum exchange between ions and dust grains, and ion-neutral collisions are taken into account. It is shown that the amplitudes of soliton-like compression and rarefaction perturbations decrease in the course of their evolution and their velocities (the Mach numbers) decrease monotonically in time. At any instant of time, the shape of an evolving soliton-like perturbation coincides with the shape of a conservative soliton corresponding to the current value of the Mach number. It is shown that, after the interaction between any types of soliton-like perturbations, their velocities and shapes are restored (with a certain phase shift) to those of the corresponding perturbations propagating without interaction; i.e., they are in fact weakly dissipative solitons.

Arbitrary dust ion acoustic soliton with streaming ions and superthermal electrons

The dynamical properties of dust-ion acoustic wave excited due to the streaming of ions and by the presence of superthermal electrons following the κ distribution function are discussed. An energy integral equation involving the Sagdeev potential is derived, and the basic properties of large amplitude solitary structures are investigated. The numerical results are elaborated by employing the parameters of mesospheric noctilucent clouds. Due to ion streaming, a regime of the existence of new solitons will take place and we found that this plays a destructive role for some of the solitons that were observable at rather lower streaming or in the absence of streaming of ions. It is also found that the presence of ion beams causes breaking up of the solitary waves into a new regime of solitons.

Cylindrical or spherical dust-ion acoustic soliton in an adiabatic dusty plasma with electrons following a q-nonextensive distribution

Using the reductive perturbation technique, a cylindrical and (or) spherical Korteweg – de Vries (KdV) equation is derived for a dust-ion acoustic solitary wave (DIASW) in an unmagnetized dusty plasma, whose constituents are adiabatic ion fluid, nonextensive electrons, and negatively charged static dust particles. The solution of the modified KdV equation in nonplanar geometry is numerically analyzed. The change of the DIASW structure due to the effect of the geometry, nonextensive parameter, dust density, and ion temperature is investigated by numerical calculation of the cylindrical and (or) spherical KdV equation. It is found that both compressive and rarefactive type DIA waves are obtained depending on the plasma parameter.

Compressive and rarefactive DIA solitons beyond the KdV limit

The modified Gardner equation (MGE), showing the existence of compressive and rarefactive dust-ion-acoustic (DIA) solitons in a nonplanar dusty plasma (containing inertial ions, Boltzmann electrons, and negatively charged stationary dust) beyond the KdV Korteweg-de Vries (KdV) limit, is derived and numerically solved. The basic features of the compressive and rarefactive cylindrical and spherical DIA solitons, which are found to exist beyond the KdV limit, i.e., exist for μ ∼ 2/3 (where μ = Z n n d0/n i0, z d is the number of electrons residing onto the dust grain surface, n d0(n i0) is the dust (ion) number density at equilibrium, and μ ∼ 2/3 means that μ is not equal to 2/3, but it is around 2/3) are identified. These solitons (which can be referred to as DIA Gardner solitons (DIA-GSs)) are completely different from the KdV solitons because μ = 2/3 corresponds to the vanishing of the nonlinear coefficient of the KdV equation, and μ ∼ 2/3 corresponds to extremely large amplitude KdV solitons for which the validity of the reductive perturbation method breaks down. It is also shown that the properties of the nonplanar (cylindrical and spherical) DIA-GSs are significantly different from those of the one dimensional planar ones.

Dust ion acoustic soliton in pair-ion plasmas with non-isothermal electrons

Dust ion acoustic (DIA) solitons in an unmagnetized pair-ion (PI) plasmas with adiabatic pair-ions, non-isothermal electrons, and negatively charged background dust are investigated, using both small and arbitrary amplitude techniques. An energy integral equation involving the Sagdeev potential is derived, and basic properties of the large amplitude solitary structures are investigated. The effects of dust concentration, resonant electrons, and ion temperatures on the profiles of the Sagdeev potential and corresponding solitary waves are studied. The related Schamel-Korteweg-de Vries (S-KdV) equation with mixed-nonlinearity is derived by expanding the Sagdeev potential. Asymptotic solutions for different orders of nonlinearity are discussed for DIA solitary waves. The present work is applicable to understand the wave phenomena and associated nonlinear electrostatic perturbations in the doped pair ion plasmas, not completely filtered e.g., pair ion-electron plasmas, enriched with an extra massive charged component (e.g., dust defects), which may be academic for the moment but might be of interest for forthcoming experiments in laboratory (space) plasmas.

Weakly dissipative dust-ion-acoustic solitons in complex plasmas and the effect of electromagnetic radiation

Possibility for dust ion-acoustic solitons to exist in complex (dusty) plasmas in the presence of electromagnetic radiation, which results in positive dust particle charges, is investigated. Dissipative processes occurring during the propagation of dust ion-acoustic perturbations, among which are the charging of dust grains, the absorption of ions by grains, the transfer of the ion momentum to the grains, and ion-neutral collisions, are taken into account. Temporal evolution of the soliton-like perturbation and interaction of two soliton-like perturbations are studied. Compressive soliton-like perturbations are shown to possess the main properties of the soltons, in particular, the interacting perturbations conserve their form.

Large amplitude solitary waves in ion-beam plasmas with charged dust impurities

The nonlinear propagation of large amplitude dust ion-acoustic (DIA) solitary waves (SWs) in an ion-beam plasma with stationary charged dusts is investigated. For typical plasma parameters relevant for experiments [Y. Nakamura and K. Komatsuda, J. Plasma Phys. 60, 69 (1998)], when the beam speed is larger than the DIA speed (νb0 ≳ 1.7cs), three stable waves, namely, the “fast” and “slow” ion-beam modes and the plasma DIA wave, are shown to exist. These modes can propagate as SWs in the beam plasmas. However, in the other regime (cs < νb0 < 1.7cs), one of the beam modes when coupled to the DIA mode may become unstable. The SWs with positive (negative) potential may exist when the difference of the nonlinear wave speed (M) and the beam speed is such that 1.2 ≲ M − νb0 ≲ 1.6 (M − νb0 ≳ 1.6). Furthermore, for real density perturbations, the wave potential ( > 0) is found to be limited by a critical value which typically depends on M, νb0 as well as the ion/beam temperature. The conditions for the existence of DIA solitons are obtained, and their properties are analyzed numerically in terms of the system parameters. While the system supports both the compressive and rarefactive large amplitude SWs, the small amplitude solitons exist only of the compressive type. The theoretical results may be useful for observation of soliton excitations in laboratory ion-beam driven plasmas as well as in space plasmas where the charged dusts play as impurities.

Effect of Dust Grains on Dust-Ion-Acoustic KdV Solitons in Magnetized Complex Plasma with Superthermal Electrons

In this paper, the propagation of dust-ion-acoustic (DIA) waves in a magnetized collisionless complex (dusty) plasma consisting of superthermal electrons are investigated. In the discharge plasma, the electron temperature is usually much greater than ion temperature. Thus, the electron distribution function DF), is generally nonmaxwellian, has to be modeled. For this purpose, the generalized Lorentzian ( $$ \kappa $$ )-DF is used to simulate the electron DF. Two types of modes (fast and slow DIA modes) exist in this plasma. By deriving Korteweg-de Vries (KdV) equation, using reductive perturbation method, both regions of solitary waves, rarefactive (dark) and compressive (bright) solitary waves, are allowed to be propagated in this plasma. Properties of DIA solitary waves are investigated numerically. How dust grains and superthermal electrons affect the sign and the magnitude of nonlinear coefficient of KdV equation is also discussed in detail. It is noted that the velocity, amplitude, and width of a DIA soliton is studied as well.

Head-on collision of dust-ion-acoustic soliton in quantum pair-ion plasma

In this paper, we study the head-on collision between two dust ion acoustic solitons in quantum pair-ion plasma. Using the extended Poincare–Lighthill–Kuo method, we obtain the Korteweg–de Vries equation, the phase shifts, and the trajectories after the head-on collision of the two dust ion acoustic solitons. It is observed that the phase shifts are significantly affected by the values of the quantum parameter H, the ratio of the multiples of the charge state and density of positive ions to that of the negative ions β and the concentration of the negatively charged dust particles δ.

Higher-order corrections to dust ion-acoustic soliton in a quantum dusty plasma

Dust ion-acoustic soliton is studied in an electron-dust-ion plasma by employing a two-fluid quantum hydrodynamic model. Ions and electrons are assumed to follow quantum mechanical behaviors in dust background. The Korteweg–de Vries (KdV) equation and higher order contribution to KdV equations are derived using reductive perturbation technique. The higher order contribution is obtained as a higher order inhomogeneous differential equation. The nonsecular solution of the higher order contribution is obtained by using the renormalization method and the particular solution of the inhomogeneous equation is determined using a truncated series solution method. The effects of dust concentration, quantum parameter for ions and electrons, and soliton velocity on the amplitude and width of the dressed soliton are discussed.

Dust ion acoustic solitons in a plasma with kappa-distributed electrons

Dust ion acoustic solitons in an unmagnetized dusty plasma comprising cold dust particles, adiabatic fluid ions, and electrons satisfying a κ distribution are investigated using both small amplitude and arbitrary amplitude techniques. Their existence domain is discussed in the parameter space of Mach number M and electron density fraction f over a wide range of values of κ. For all κ>3/2, including the Maxwellian distribution, negative dust supports solitons of both polarities over a range in f. In that region of parameter space solitary structures of finite amplitude can be obtained even at the lowest Mach number, the acoustic speed, for all κ. These cannot be found from small amplitude theories. This surprising behavior is investigated, and it is shown that fc, the value of f at which the KdV coefficient A vanishes, plays a critical role. In the presence of positive dust, only positive potential solitons are found.

Evolution of weakly dissipative hybrid dust ion-acoustic solitons in complex plasmas

Possibility for hybrid ion-acoustic solitons to exist in complex (dusty) plasmas is investigated. Rarefactive solitonlike perturbations are damped and slowed down, mainly due to the plasma absorption and ion scattering on microparticles. Nevertheless, the amplitude of the evolving perturbation at any moment is given by the amplitude of the “conservative” soliton for the corresponding Mach number (so far as the conservative soliton exists). That property allows us to interpret the evolving rarefactive perturbation as a “weakly dissipative” hybrid dust ion-acoustic soliton. The weakly dissipative hybrid dust ion-acoustic solitons can be studied experimentally in laboratory complex plasmas.

A proposal for dust-ion-acoustic soliton excitation in a discharge plasma

Nonlinear dynamics of disintegration process of a localized perturbation into dust-ion-acoustic (DIA) solitons is studied. The present paper is a theoretical attempt to propose and model the experimental DIA soliton excitation [Y. Nakamura and A. Sarma, Phys. Plasmas 8, 3921 (2001)] in the presence of both superthermal and trapped electrons. The proposal is designed for low-pressure electrical gas discharges that are in nonequilibrium state. In the discharge plasmas, the electron temperature is usually much greater than ion temperature. Thus, the electron distribution function (DF) that in low-pressure discharges is generally non-Maxwellian has to be modeled. For this purpose, the generalized Lorentzian (κ)-DF is used to simulate the electron DF. The formalism is derived near the ion-plasma frequency. In this range of frequency, the ion dynamics is considerable and the DIA solitons are the outcome of the disintegration process. Electron trapping is included in the model as the result of positive polarity of the initial potential. A Gaussian initial perturbation is used to model the localized perturbation. It is shown that a slowly varying dynamics of the order of ion motions causes an initial Gaussian perturbation to be, adiabatically, disintegrated to a number of DIA solitons. The disintegration attributes and influence of both trapped and superthermal electrons on this process, are studied.

Dust-ion-acoustic solitons in plasmas with non-Maxwellian electron distribution function

Stationary dust-ion-acoustic (DIA) solitons in plasma with non-Maxwellian electron distribution function (DF) are studied. This is an important issue in low-pressure electrical gas discharges that the particle DF is generally non-Maxwellian. In the discharge plasmas, the electron temperature is usually much greater than the ion temperature. Thus, neglecting the ions velocity distribution, the electron DF is modeled by the generalized Lorentzian (κ)-DF. The formalism is derived near the ion-plasma frequency. In this range of frequency, the ion dynamics is considerable and the dust-ion-acoustic solitons are the stationary solution of the governing equations. Electron trapping is included in the model as the result of nonlinear resonant interaction of the DIA soliton with electrons. The solitons attributes and influence of the non-Maxwellian electrons are studied.

Effects of ion-fluid temperature on dust-ion-acoustic solitons

The properties of dust-ion-acoustic (DIA) solitons in an unmagnetized dusty plasma, whose constituents are adiabatic ion-fluid, Boltzmann electrons, and static dust particles, are investigated by employing the reductive perturbation method. The Korteweg-de Vries equation is derived and its stationary solution is numerically analyzed. The parametric regimes for the existence of positive and negative solitons are found. It has been shown that ion-fluid temperature not only significantly modifies the basic features (width and amplitude) of DIA solitons, but also introduces some new features of DIA solitons.

Existence domains for nonlinear structures in complex two-ion-temperature plasmas

The existence domains for one-dimensional acoustic solitons and double layers in complex (dusty) plasmas with two ion temperatures are obtained, using the fluid dynamic paradigm with a general polytropic equation of state. Dust-acoustic solitons are considered in a four-component plasma of negative dust grains, cool and very hot ions, and very hot electrons. Whereas in a dust-ion-electron plasma only negative potential solitons are supported, the presence of a second ion component allows positive potential solitons to occur as well. The existence domain in parameter space is delineated, in particular, also for the reduced three-component case in which there are no free electrons, all electrons being adsorbed onto the dust grains. Next, the ion-acoustic regime is considered. Both positive and negative potential dust-ion acoustic solitons and double layers are found, and their existence conditions in the parameter space of cool ion density and Mach number derived.

Dust–ion–acoustic solitons and shocks in dusty plasmas

Abstract Propagation of nonlinear dust–ion–acoustic waves (DIAWs) has been investigated considering the effects of charge fluctuation dynamics of stationary dust particles, transverse perturbations, ion streaming velocity and ions to electrons temperature ratio. By using the reductive perturbation theory, Kadomtsev–Petviashivili–Burgers (KPB) equation is derived. It is found that both solitons or shocks may appear in the system depending on the anomalous dissipation from dust particles charging process, whereas transverse perturbations, ion streaming velocity and ions to electrons temperature ratio are responsible for the stability of the solitons.