Modulated envelope localized wavepackets associated with electrostatic plasma waves

非麦克斯韦等离子体中作为 rogue wave 形成前兆的通过不对称向量孤子实现的静电波相互作用

Electrostatic wave interaction via asymmetric vector solitons as precursor to rogue wave formation in non-Maxwellian plasmas

通过多尺度微扰法推导出非麦克斯韦等离子体中的不对称耦合非线性薛定谔方程，揭示了调制不稳定性作为亮型包络激发和 freak waves 形成前兆的作用。

Dust ion-acoustic dromions in Saturn's magnetosphere

Motivated by observations of localized electrostatic wavepackets by the Cassini and (earlier) by Voyager 1 and 2 mission(s) in Saturn's magnetosphere, we have investigated the existence conditions and the dynamical evolution of localized multi-dimensional structures in the Saturnian dusty plasma environment. To this effect, we have adopted a plasma-fluid model for dust-ion acoustic (DIA) excitations, taking into account the presence of a highly energetic (suprathermal, kappa-distributed) electron population in combination with massive dust particulates in the background. A multiple scales pert…

Nonlinear Landau damping and modulation of electrostatic waves in a nonextensive electron-positron-pair plasma

The nonlinear theory of amplitude modulation of electrostatic wave envelopes in a collisionless electron-positron (EP) pair plasma is studied by using a set of Vlasov-Poisson equations in the context of Tsallis' $q$-nonextensive statistics. In particular, the previous linear theory of Langmuir oscillations in EP plasmas [Phys. Rev. E {\bf87}, 053112 (2013)] is rectified and modified. Applying the multiple scale technique (MST), it is shown that the evolution of electrostatic wave envelopes is governed by a nonlinear Schr{ö}dinger (NLS) equation with a nonlocal nonlinear term $\propto {\cal{P}}…

Modulational instability and nonlinear evolution of two-dimensional electrostatic wave packets in ultra-relativistic degenerate dense plasmas

We consider the nonlinear propagation of electrostatic wave packets in an ultra-relativistic (UR) degenerate dense electron-ion plasma, whose dynamics is governed by the nonlocal two-dimensional nonlinear Schr{ö}dinger-like equations. The coupled set of equations are then used to study the modulational instability (MI) of a uniform wave train to an infinitesimal perturbation of multi-dimensional form. The condition for the MI is obtained, and it is shown that the nondimensional parameter, $β\proptoλ_C n_0^{1/3}$ (where $λ_C$ is the reduced Compton wavelength and $n_0$ is the particle number de…

Simulation study of the interaction between large-amplitude HF radio waves and the ionosphere

The time evolution of a large-amplitude electromagnetic (EM) wave injected vertically into the overhead ionosphere is studied numerically. The EM wave has a carrier frequency of 5 MHz and is modulated as a Gaussian pulse with a width of approximately 0.1 milliseconds and a vacuum amplitude of 1.5 V/m at 50 km. This is a fair representation of a modulated radio wave transmitted from a typical high-power HF broadcast station on the ground. The pulse is propagated through the neutral atmosphere to the critical points of the ionosphere, where the L-O and R-X modes are reflected, and back to the ne…

A new (2+1) dimensional integrable evolution equation for an ion acoustic wave in a magnetized plasma

A new, completely integrable, two dimensional evolution equation is derived for an ion acoustic wave propagating in a magnetized, collisionless plasma. The equation is a multidimensional generalization of a modulated wavepacket with weak transverse propagation, which has resemblance to nonlinear Schrodinger (NLS) equation and has a connection to Kadomtsev-Petviashvili equation through a constraint relation. Higher soliton solutions of the equation are derived through Hirota bili- nearization procedure, and an exact lump solution is calculated exhibiting 2D structure. Some mathe- matical proper…

Modulation of drift-wave envelopes in a nonuniform quantum magnetoplasma

We study the amplitude modulation of low-frequency, long-wavelength electrostatic drift-wave envelopes in a nonuniform quantum magnetoplasma consisting of cold ions and degenerate electrons. The effects of tunneling associated with the quantum Bohm potential and the Fermi pressure for nonrelativistic degenerate electrons, as well as the equilibrium density and magnetic field inhomogeneities are taken into account. Starting from a set of quantum magnetohydrodynamic (QMHD) equations, we derive a nonlinear Schrödinger equation (NLSE) that governs the dynamics of the modulated quantum drift-wave p…

How Electron Two-Stream Instability Drives Cyclic Langmuir Collapse and Continuous Coherent Emission

Continuous plasma coherent emission is maintained by repetitive Langmuir collapse driven by the nonlinear evolution of a strong electron two-stream instability. The Langmuir waves are modulated by solitary waves in the linear stage, and by electrostatic whistler waves in the nonlinear stage. Modulational instability leads to Langmuir collapse and electron heating that fills in cavitons. The high pressure is released via excitation of a short wavelength ion acoustic mode that is damped by electrons and that re-excites small-scale Langmuir waves---this process closes a feedback loop that maintai…

Weakly nonlinear vertical dust grain oscillations in dusty plasma crystals in the presence of a magnetic field

The weakly nonlinear regime of transverse paramagnetic dust grain oscillations in dusty (complex) plasma crystals is discussed. The nonlinearity, which is related to the sheath electric/magnetic field(s) and to the inter--grain (electrostatic/magnetic dipole) interactions, is shown to lead to the generation of phase harmonics and, in the case of propagating transverse dust-lattice modes, to the modulational instability of the carrier wave due to self--interaction. The stability profile depends explicitly on the form of the electric and magnetic fields in the plasma sheath. The long term evolut…