Modulational instability of ion acoustic wave with warm ions in electron-positron-ion plasmas

Abstract

The nonlinear amplitude modulation of ion acoustic wave is studied in the presence of warm ions in unmagnetized electron-positron-ion plasmas. The Krylov-Bogoliubov-Mitropolsky (KBM) method is used to derive the nonlinear Schrödinger equation. The dispersive and nonlinear coefficients are obtained which depends on the ion temperature and positron density in electron-positron-ion plasmas. The modulationally stable and unstable regions are studied numerically for a wide range of wave number. It is found that both ion temperature and positron density play a significant role in the formation of bright and dark envelope solitons in electron-positron-ion plasmas.

Effect of ion temperature on modulational instability and envelope solitons of ion acoustic waves in nonthermal electron–positron–ion plasmas

“…The observations of modulational instability for the monochromatic ion acoustic waves have been reported in experiment [45]. The modulational instability in unmagnetized epi plasmas with warm ions for Maxwellian electrons and positrons has also been investigated [46]. In the presence of ion temperature in epi plasmas, the modulated ion acoustic waves have two values of critical wave numbers instead of one in the cold ion case.…”

Numerical simulation on modulational instability of ion-acoustic waves in plasma

“…Due to this, the modulational stability can be investigated in terms of characteristic parameters, including the wave number k. Presently, investigations into some electrostatic (ES) modes have already been investigated. [8,9] To date, the modulational instability of different wave modes in plasmas has received a great deal of interest, [10][11][12][13] for example, the modulational instability of the monochromatic ion-acoustic wave (IAW) has generally been described using the NLSE from the resultant equations of the reductive perturbation theory. [14][15][16] Their corresponding experimental observations were first reported by Watanabe.…”

Electrostatic vortex structures in a rotating magnetized electron-positron plasma with stationary ions

“…Different types of nonlinear structures such as solitons, envelope holes, shocks and vortices, etc., in e-p-i plasmas have been investigated. [13][14][15][16][17][18][19][20][21][22][23] The wave spectrum of e-p plasmas also gets broaden with the inclusion of ions because now both slow and fast range of frequencies are available in e-p-i plasmas. The nonlinear dynamics of convective motion in a rotating magnetized e-p plasma has been studied by Shukla et al 24 They investigated that equilibrium radial electric field is produced in a rotating plasma due to Coriolis force effect which balances the Lorentz force term.…”