Stability of oblique modulation of ion-acoustic waves in a multicomponent plasma

Abstract

The stability of oblique modulation of ion-acoustic waves in a collisionless plasma consisting of two cold-ion species with different masses, concentrations, and charge states, and hot isothermal electrons is studied. Using the Krylov–Bogoliubov–Mitropolosky (KBM) perturbation technique, a nonlinear Schrödinger equation governing the slow modulation of the wave amplitude, is derived for the system. It is found that the presence of second-ion species significantly changes the instability domain in the k-φ plane. The effect of charge state, concentration, and mass of second-ion species on the modulational instability is discussed in detail. The predictions of the theory are found to be in good agreement with the experimental observations.

Stability of oblique modulation of dust-acoustic waves in a warm dusty plasma with dust charge variation

“…The oblique modulational instability of the IAW has been recently studied by many authors. [3][4][5]7 Including the heavily charged dust grains, however, means that the corresponding physical effects of dusty plasma are basically distinct compared to the ion plasma system. The presence of the charged dust grains in a plasma can modify the collective behavior of a plasma, as well as excite new modes.…”

“…[1][2][3][4][5][6][7][8] The slow modulation of a monochromatic plane wave in plasmas can lead to the formation of envelope solitons, which are described by the nonlinear Schrödinger equation ͑NLSE͒. In the NLSE, the nonlinearities are in balance with the wave group dispersion and the resulting stationary solutions of the NLSE have an envelope structure.…”

Exact theory for localized envelope modulated electrostatic wavepackets in space and dusty plasmas

“…The amplitude modulation direction (∼x) is assumed "oblique" with respect to the (arbitrary) propagation direction, which is expressed by the wave vector k = (k x , k y ) = (k cos θ, k sin θ) ; cf. (Kako and Hasegawa, 1976;Chhabra and Sharma, 1986;Mishra et al, 1994), where a similar treatment is adopted. Note that (not having taken the magnetic field into account in the analysis) this is essentially a "2d" physical problem, although readily applicable in a three-dimensional ("3d") description, for completeness.…”

Dynamics of modulationally unstable ion-acoustic wavepackets in plasmas with negative ions

“…The nonlinear Schrödinger equation describing the nonlinear evolution of modulations of a harmonic carrier wave can be derived directly from the system of equations (2.1). A similar derivation has been performed for ion-electron plasmas by, e.g., Chan and Seshadri (1975), for ionelectron plasmas with two populations of electron with different temperatures by Kourakis and Shukla (2003a), for plasmas with negative ions by Saito et al (1984), and for multicomponent plasma by, e.g., Mishra et al (1994) (see also the derivation of the nonlinear Schrödinger equation for dusty plasma by Shukla (2003b, 2005)). In all of these papers the derivation of the nonlinear Schrödinger equation has been carried out for arbitrary frequency of the carrier wave.…”