Nonlinear wave modulation of cylindrical and spherical quantum ion-acoustic solitary waves

Cylindrical and spherical amplitude modulation of quantum ion-acoustic (QIA) envelope solitary waves in a dense quantum plasma comprised of electrons and ions is investigated. For this purpose, a one-dimensional quantum hydrodynamic model and the Poisson equation are considered. By using the standard reductive perturbation technique, a modified nonlinear Schrödinger equation with the geometrical and the quantum effects is derived. The effect of quantum corrections and the effect due to the cylindrical and spherical geometries on the propagation of the QIA envelope solitary waves are examined. It is shown that there exists a modulation instability period depending on the quantum parameter, which does not exist for the one-dimensional classical case

Arbitrary amplitude dust acoustic solitary waves in a dusty plasma with an ion beam

Propagation regimes of an arbitrary amplitude dust acoustic solitary wave in a dusty plasma with an ion beam are analyzed by employing the Sagdeev potential technique. Two domains of the Mach numbers are defined depending on the ion beam and plasma parameters. Only a rarefactive soliton solution is found in a low velocity regime. Numerical solutions are presented that illustrate the dependence of soliton characteristics on practically interesting plasma and ion beam parameters. The findings of this investigation could be useful in understanding the nonlinear interaction of external ion beam and dusty plasma observed in laboratory plasma experiments