Evolution of ion–ion acoustic instability in multi-ion plasma sheaths
- 95 Downloads
The generation of ion-acoustic solitary waves is investigated in a nonuniform multicomponent collisional plasma sheath containing cold ions and Boltzmann electrons to probe the formation and physics of modulation of nonlinear ion-acoustic waves. The new model for the plasma is adapted to include the effects of ion production-loss and momentum loss terms due to ion-neutral collisions, and implementation related to space and laboratory plasma applications are discussed. The discrete modes, the instability conditions and the growth rate of the streaming instability with the effect of the present plasma parameters are calculated based on the approximate but yet precise complex dispersion relation. The marginal stability curve, characterized by mode bifurcation, cutoff, and complex fold point, indicates a growth rate of a few percents of effective plasma frequency. The damping of ion-acoustic is affected by heavy neutrals, and its maximum rate found near the ion-neutral collision frequency. The variable-coefficient Korteweg-de Vries equation is derived via reductive perturbation method to govern the dynamics of small- as well as large-amplitude solitons. It is found that the propagating nonlinear coherent structures through the created ion phase-space vortices lead to ion trapping and acceleration, and the modulation of ion-acoustic instabilities in the turbulent region. The effect of ion streaming motion on the driven solitons and modulation instability for the variable-coefficient Korteweg-de Vries equation is numerically investigated in detail. The theoretical results can be applied to the observation of electrostatic waves in space plasmas, in industrial pair-ion plasmas as well as in laboratory dusty plasmas.
KeywordsIon-beam-plasma Ion-acoustic solitary waves Modulation instability Ion acceleration
All data for this paper are properly cited and referred to in the reference list.
Compliance with ethical standards
Conflict of interest
The author confirms that this paper content has no conflict of interest.
- 6.Akhiezer, A.I., Akhiezer, I.A., Polovin, R.V., Sitenko, A.G., Stepanov, K.W.: Plasma ELectrodynamics: Linear Theory, 2nd edn. Pergamon Press, Oxford (1975)Google Scholar
- 27.Zaqarshvili, T.V., Khodachenko, M.L., Rucker, H.O.: Damping of Alfvén waves in solar partially ionized plasmas: effect of neutral helium in multi-fluid approach. Astron. Astrophys. 534(A93), 1–7 (2011)Google Scholar
- 30.Yau, A.W., Lockwood, M.: Vertical ion flow in the polar ionosphere. In: Moore, T.E., Waite, J.H., Moorehead, T.W., Hanson, W.B. (eds.) pp. 229–240. American Geophysical Union, Washington (2013)Google Scholar
- 34.Wazwaz, A.M.: Chapter 9, the kdv equation. In: Dafermos, C.M., Pokorny, M. (eds.) Handbook of Differential Equations: Evolutionary Equations, vol. 4, 1st edn, pp. 485–568. North-Holland, Amsterdam (2008)Google Scholar
- 37.Lifshitz, E.M., Pitaevskii, L.P.: Physical Kinetics. Butterworth-Heinemann, Oxford (1981)Google Scholar