Modulational instability, rogue waves, and envelope solitons in opposite polarity dusty plasmas

TL;DR

This paper investigates the modulational instability of dust-acoustic waves in opposite polarity dusty plasmas, revealing conditions for dark and bright envelope solitons and rogue waves influenced by plasma parameters.

Contribution

It derives a nonlinear Schrödinger equation for dust-acoustic waves in a complex plasma system with non-extensive electrons and non-thermal ions, analyzing stability and rogue wave formation.

Findings

Dark envelope solitons occur in stable regimes.

Bright envelope solitons and rogue waves occur in unstable regimes.

Plasma parameters significantly affect wave stability and rogue wave characteristics.

Abstract

Dust-acoustic (DA) waves (DAWs) and their modulational instability (MI) have been investigated theoretically in a plasma system consisting of inertial opposite polarity (positively and negatively) warm adiabatic charged dust particles as well as inertialess non-extensive $q$-distributed electrons and non-thermal ions. A nonlinear Schr\"{o}dinger (NLS) equation is derived by using the reductive perturbation method. It has been observed from the analysis of NLS equaion that the modulationally stable solitary DAWs give rise to the existence of dark envelope solitons, and that the modulationally unstable solitary DAWs give rise to the existence of bright envelope solitons or rogue structures. It is also observed for the fast mode of DAWs that the basic features (viz. stability of the DAWs, MI growth rate, amplitude and width of the DA rogue waves, etc.) are significantly modified by the related plasma parameters (viz. dust masses, dust charge state, non-extensive parameter $q$, and non-thermal parameter $\alpha$). The results of our present investigation might be useful for understanding different nonlinear electrostatic phenomena in both space (viz. ionosphere and mesosphere) and laboratory plasmas (viz. high intensity laser irradiation and hot cathode discharge).