Nonlinear ion-acoustic solitons in a magnetized quantum plasma with arbitrary degeneracy of electrons

Abstract

Nonlinear ion-acoustic waves are analyzed in a nonrelativistic magnetized quantum plasma with arbitrary degeneracy of electrons. Quantum statistics is taken into account by means of the equation of state for ideal fermions at arbitrary temperature. Quantum diffraction is described by a modified Bohm potential consistent with finite-temperature quantum kinetic theory in the long-wavelength limit. The dispersion relation of the obliquely propagating electrostatic waves in magnetized quantum plasma with arbitrary degeneracy of electrons is obtained. Using the reductive perturbation method, the corresponding Zakharov-Kuznetsov equation is derived, describing obliquely propagating two-dimensional ion-acoustic solitons in a magnetized quantum plasma with degenerate electrons having an arbitrary electron temperature. It is found that in the dilute plasma case only electrostatic potential hump structures are possible, while in dense quantum plasma, in principle, both hump and dip soliton structures are obtainable, depending on the electron plasma density and its temperature. The results are validated by comparison with the quantum hydrodynamic model including electron inertia and magnetization effects. Suitable physical parameters for observations are identified.

Coupling between ion-acoustic waves and neutrino oscillations

“…Finally, the plasma can be also taken as non-degenerate to reasonable accuracy, with a Fermi energy E F = 2 (3 π 2 n 0 ) 2/3 /(2 m e ) = 78.76 keV < κ B T e . To include degeneracy effects, the equation of state of an isothermal degenerate Fermi gas would be required, with the net effect [15,16] of the replacement of c s by a generalized ion-acoustic velocity C s given by…”

Two‐dimensional magnetosonic shock wave propagation in dense electron–positron–ion plasmas

“…[18][19][20][21][22][23] This Bohm force term is responsible for quantum tunnelling effects in a quantum plasma associated with electrons and positrons due to their wave-like nature. In case of a non-degenerate plasma, → 1, while for the fully degenerate electrons/positrons case, = 1/3 for low-frequency waves such as ion-acoustic waves and = 3 for high-frequency waves such as quantum Langmuir waves, which gives the Bohm-Pines dispersion relation.…”

“…In case of a non-degenerate plasma, → 1, while for the fully degenerate electrons/positrons case, = 1/3 for low-frequency waves such as ion-acoustic waves and = 3 for high-frequency waves such as quantum Langmuir waves, which gives the Bohm-Pines dispersion relation. [18][19][20][21][22][23] This Bohm force term is responsible for quantum tunnelling effects in a quantum plasma associated with electrons and positrons due to their wave-like nature. In our low-frequency plasma case, we have = 1/3.…”

Magnetosonic waves in a quantum plasma with arbitrary electron degeneracy

“…Using classical kinetic theory, and linearizing the Vlasov-Poisson system around a Fermi-Dirac equilibrium, Maafa [18] was the first to study ion-acoustic and Langmuir waves in plasmas with arbitrary degeneracy of electrons. Recently, Haas and Mahmood [13,19] investigated the linear and nonlinear ion-acoustic waves unmagnetized (one-dimensional soliton) and magnetized (two-dimensional soliton) in dense plasma with arbitrary degeneracy of electrons. The quantum coupling parameter is defined for an arbitrary degenerate plasma, with limitations for the quantum diffraction parameter in quantum hydrodynamic (QHD) models.…”