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1.	Stenflo, Lennart, et al. (author) Nonlinear beam generated plasma waves as a source for enhanced plasma and ion acoustic lines 2011 In: Physics of Plasmas. - : American Institute of Physics (AIP). - 1070-664X .- 1089-7674. ; 18:15, s. 052107-1-052107-14 Journal article (peer-reviewed)abstract Observations by, for instance, the EISCAT Svalbard Radar (ESR) demonstrate that the symmetry of the naturally occurring ion line in the polar ionosphere can be broken by an enhanced, nonthermal, level of fluctuations (naturally enhanced ion-acoustic lines, NEIALs). It was in many cases found that the entire ion spectrum can be distorted, also with the appearance of a third line, corresponding to a propagation velocity significantly slower than the ion acoustic sound speed. It has been argued that selective decay of beam excited primary Langmuir waves can explain some phenomena similar to those observed. We consider a related model, suggesting that a primary nonlinear process can be an oscillating two-stream instability, generating a forced low frequency mode that does not obey any ion sound dispersion relation. At later times, the decay of Langmuir waves can give rise also to enhanced asymmetric ion lines. The analysis is based on numerical results, where the initial Langmuir waves are excited by a cold dilute electron beam. By this numerical approach, we can detect fine details of the physical processes, in particular, demonstrate a strong space-time intermittency of the electron waves in agreement with observations. Our code solves the full Vlasov equation for electrons and ions, with the dynamics coupled through the electrostatic field derived from Poisson's equation. The analysis distinguishes the dynamics of the background and beam electrons. This distinction simplifies the analysis for the formulation of the weakly nonlinear analytical model for the oscillating two-stream instability. The results have general applications beyond their relevance for the ionospheric observations.
2.	Brodin, Gert, et al. (author) Three-wave coupling coefficients for a magnetized plasma 2012 In: Physica Scripta. - Bristol : Institute of Physics. - 0031-8949 .- 1402-4896. ; 85:3, s. 035504- Journal article (peer-reviewed)abstract The resonant interaction between three waves in a uniform magnetized plasma is reconsidered. Starting from previous kinetic expressions, which contain a general but too little used result, we are able to improve the formulae. This leads to an explicit expression for the three-wave coupling coefficient which applies for arbitrary wave propagation in a magnetized Vlasov plasma.
3.	Brodin, Gert, et al. (author) A new decay channel for upper-hybrid waves 2016 In: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 91:10 Journal article (peer-reviewed)abstract We look here at a three-wave interaction process involving only electrostatic waves in an electron plasma with stationary ions. Special attention is given to the case with an upper-hybrid wave as a pump wave, where a new decay channel is pointed out. The corresponding growth rate is calculated.
4.	Brodin, Gert, et al. (author) A simple electron plasma wave 2017 In: Physics Letters A. - : Elsevier BV. - 0375-9601 .- 1873-2429. ; 381:11, s. 1033-1035 Journal article (peer-reviewed)abstract Considering a class of solutions where the density perturbations are functions of time, but not of space, we derive a new exact large amplitude wave solution for a cold uniform electron plasma. This result illustrates that most simple analytical solutions can appear even if the density perturbations are large.
5.	Brodin, Gert, et al. (author) Alfven wave interactions within the Hall-MHD description 2013 In: Journal of Plasma Physics. - : Cambridge University Press (CUP). - 0022-3778 .- 1469-7807. ; 79, s. 909-911 Journal article (peer-reviewed)abstract We show that comparatively simple expressions for the Alfven wave coupling coefficients can be deduced from the well-known Hall-magnetohydrodynamics (MHD) model equations.
6.	Brodin, Gert, et al. (author) Focus issue to honour Hans L Pecseli on his 70th birthday 2017 In: Physica Scripta. - : IOP PUBLISHING LTD. - 0031-8949 .- 1402-4896. ; 92:1 Journal article (other academic/artistic)abstract n/a
7.	Brodin, Gert, et al. (author) Large amplitude electron plasma oscillations 2014 In: Physics Letters A. - : Elsevier. - 0375-9601 .- 1873-2429. ; 378:22-23, s. 1632-1635 Journal article (peer-reviewed)abstract We consider a cold plasma in order to find new large-amplitude wave solutions in the long-wavelength limit. Accordingly we derive two generic coupled equations which describe the energy exchange between the electrostatic and electromagnetic waves. A new kind of quasi-periodic behavior is found. Our derivations may be considered as a prerequisite to extended studies of stimulated Raman scattering for cases where the wave amplitudes are so large that standard perturbation techniques are not applicable.
8.	Brodin, Gert, et al. (author) Nonlinear dynamics of a cold collisional electron plasma 2017 In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 24:12 Journal article (peer-reviewed)abstract We study the influence of collisions on the dynamics of a cold non-relativistic plasma. It is shown that even a comparatively small collision frequency can significantly change the large amplitude wave solution.
9.	Brodin, Gert, et al. (author) Nonlinear dynamics of large amplitude modes in a magnetized plasma 2014 In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 21:12 Journal article (peer-reviewed)abstract We derive two equations describing the coupling between electromagnetic and electrostatic oscillations in one-dimensional geometry in a magnetized cold and non-relativistic plasma. The nonlinear interaction between the wave modes is studied numerically. The effects of the external magnetic field strength and the initial electromagnetic polarization are of particular interest here. New results can, thus, be identified.
10.	Brodin, Gert, et al. (author) Nonlinear wave interactions of kinetic sound waves 2015 In: Annales Geophysicae. - : Copernicus GmbH. - 0992-7689 .- 1432-0576. ; 33:8, s. 1007-1010 Journal article (peer-reviewed)abstract We reconsider the nonlinear resonant interaction between three electrostatic waves in a magnetized plasma. The general coupling coefficients derived from kinetic theory are reduced here to the low-frequency limit. The main contribution to the coupling coefficient we find in this way agrees with the coefficient recently presented in Annales Geophysicae. But we also deduce another contribution which sometimes can be important, and which qualitatively agrees with that of an even more recent paper. We have thus demonstrated how results derived from fluid theory can be improved and generalized by means of kinetic theory. Possible extensions of our results are outlined.
11.	Brodin, Gert, 1963-, et al. (author) On the parametric decay of waves in magnetized plasmas 2009 In: Journal of Plasma Physics. - Cambridge UK : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 75, s. 9-13 Journal article (other academic/artistic)abstract We reconsider the theory for three-wave interactions in cold plasmas. In particular, we demonstrate that previously overlooked formulations of the general theory are highly useful when deriving concrete expressions for specific cases. We also pointout that many previous results deduced directly from the basic plasma equations contain inappropriate approximations leading to unphysical results. Finally, generalizations to more elaborate plasma models containing, for example, kinetic effects are given.
12.	Brodin, Gert, 1963-, et al. (author) Stimulated Brillouin scattering in magnetized plasmas 2013 In: Journal of Plasma Physics. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 79:Special Issue 06, s. 983-986 Journal article (peer-reviewed)abstract Previous theory for stimulated Brillouin scattering is reconsidered and generalized. We introduce an effective ion sound velocity that turns out to be useful in describing scattering instabilities.
13.	Brodin, Gert, et al. (author) Three-wave coupling coefficients for perpendicular wave propagation in a magnetized plasma 2015 In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 22:10 Journal article (peer-reviewed)abstract The resonant interaction between three waves in a uniform magnetized plasma is reconsidered. Starting from previous kinetic expressions, we limit our investigation to waves propagating perpendicularly to the external magnetic field. It is shown that reliable results can only be obtained in the two-dimensional case, i.e., when the wave vectors have both x and y components.
14.	Brodin, Gert, et al. (author) Wave Generation in a Warm Magnetized Multi-Component Plasma 2014 In: Contributions to Plasma Physics. - : Wiley. - 0863-1042 .- 1521-3986. ; 54:7, s. 623-625 Journal article (peer-reviewed)abstract The resonant interaction between three waves propagating perpendicularly to an external magnetic field in a plasma is considered. We present the explicit expressions for the three wave coupling coefficients of a warm multi-component plasma. The results of previous work on the generation of THz radiation by laser plasma interaction are significantly improved. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
15.	Dieckmann, Mark E, 1969-, et al. (author) Simulation study of the filamentation of counter-streaming beams of the electrons and positrons in plasmas 2009 In: Plasma Physics and Controlled Fusion. - : Institute of Physics Publishing (IOPP). - 0741-3335 .- 1361-6587. ; 51:6 Journal article (peer-reviewed)abstract The filamentation instability (FI) driven by two spatially uniform and counter-streaming beams of charged particles in plasmas is modelled by a particle-in-cell simulation. Each beam consists of electrons and positrons. The four species are equally dense and have the same temperature. The one-dimensional simulation direction is orthogonal to the beam velocity vector. The magnetic field grows spontaneously and rearranges the particles in space, such that the distributions of the electrons of one beam and the positrons of the second beam match. The simulation demonstrates that as a result no electrostatic field is generated by the magnetic field through its magnetic pressure gradient prior to its saturation. This electrostatic field would be repulsive at the centres of the filaments and limit the maximum charge and current density. The filaments of electrons and positrons in this simulation reach higher charge and current densities than in one with no positrons. The oscillations of the magnetic field strength induced by the magnetically trapped particles result in an oscillatory magnetic pressure gradient force. The latter interplays with the statistical fluctuations in the particle density and it probably enforces a charge separation, by which electrostatic waves grow after the FI has saturated.
16.	Eliasson, Bengt, et al. (author) Full-scale simulation study of stimulated electromagnetic emissions: The first ten milliseconds 2010 In: JOURNAL OF PLASMA PHYSICS. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 76, s. 369-375 Journal article (peer-reviewed)abstract A full-scale numerical study is performed of the nonlinear interaction between a large-amplitude electromagnetic wave and the Earths ionosphere; and of the stimulated electromagnetic emission emerging from the turbulent layer, during the first 10 milliseconds after switch-on of the radio transmitter. The frequency spectra are downshifted in frequency and appear to emerge from a region somewhat below the cutoff of the O mode, which is characterized by Langmuir wave turbulence and localized Langmuir envelopes trapped in ion density cavities. The spectral features of escaping O-mode waves are very similar to those observed in experiments. The frequency components of Z-mode waves, trapped in the region between the O- and Z-mode cutoffs show strongly asymmetric and downshifted spectra.
17.	Eliasson, Bengt, et al. (author) Full-scale simulation study of the initial stage of ionospheric turbulence 2008 In: Journal of Geophysical Research. - : American Geophysical Union (AGU). - 0148-0227 .- 2156-2202. ; 113:0148-0227, s. A02305-1-A02305-9 Journal article (peer-reviewed)abstract We present a full-scale simulation of the nonlinear interaction between an intense electromagnetic wave and the Earth's ionosphere, by means of a generalized Zakharov model. The radio wave propagates from the neutral atmosphere into the ionospheric plasma layer and reaches the turning points of the ordinary and extraordinary wave modes. At the turning point of the ordinary mode, a parametric instability takes place in which the electromagnetic wave decays into an electron plasma wave and an ion acoustic wave with a typical wavelength of one meter. This is followed by collapse and caviton formation and trapping of the intense electron plasma wave. The cavitons lead to an efficient excitation of slow X (or Z) waves that propagate further into the denser ionospheric layer at higher altitudes. We use a realistic ion (oxygen) mass, length scales, and other plasma parameters. This numerical study should be useful for understanding the nonlinear interaction between intense radio waves and the ionosphere.
18.	Kaladze, T D, et al. (author) Acoustic-gravity waves in the Earths ionosphere 2008 In: Journal of Atmospheric and Solar-Terrestrial Physics. - : Elsevier BV. - 1364-6826 .- 1879-1824. ; 70:13, s. 1607-1616 Journal article (peer-reviewed)abstract Taking into account the existence of charged particles in the Earths ionosphere the propagation of acoustic-gravity waves is investigated. The influence of the Coriolis force is also taken into account. The weakly ionized ionospheric D, E, and F-layers are considered. The existence of a cut-off frequency at 2 Omega(0) (Omega(0) is the value of the angular velocity of the Earths rotation) is noted. It is shown that the linear waves are damped because of the Pedersen conductivity. When the acoustic-gravity waves are excited by external events (volcanic eruptions, earthquakes, lightning strikes, etc.) their amplitudes grow until self-organization of these waves into nonlinear vortex solitary structures is admitted. Taking into account the interaction of the induced ionospheric current with the geomagnetic field the governing nonlinear equations are deduced. The formation of dipole vortex solitary structures of low-frequency internal gravity waves is shown for the stable stratified ionosphere. The dynamic energy equation for such nonlinear structures is obtained. It is shown that nonlinear solitary vortical structures damp due to joule losses.
19.	Karimov, AR, et al. (author) Flow oscillations in radial expansion of an inhomogeneous plasma layer 2011 In: Physics Letters A. - : Elsevier BV. - 0375-9601 .- 1873-2429. ; 375:27, s. 2629-2636 Journal article (peer-reviewed)abstract The cylindrically symmetric radial evolution of an inhomogeneous plasma layer expanding into vacuum is investigated nonperturbatively by first determining the spatial structure of the plasma flow structure. The evolution is then governed by a set of ordinary differential equations. The effect of the plasma inhomogeneity on the nonlinear coupling among the electron and ion flow components and oscillations is investigated
20.	Karimov, A R, et al. (author) Coupled azimuthal and radial flows and oscillations in a rotating plasma 2009 In: PHYSICS OF PLASMAS. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 16:6, s. 062313- Journal article (peer-reviewed)abstract Nonlinear coupling between the radial, axial, and azimuthal flows in a cold rotating plasma is considered nonperturbatively by first constructing a basis solution for a rotating flow. Simple but exact solutions that describe an expanding plasma with oscillatory flow fields are then obtained. These solutions show that the energy in the radial and axial flow components can be transferred to the azimuthal component but not the vice versa. Nonlinear electron velocity oscillations in the absence of electron density oscillations at the same frequency are shown to exist.
21.	Karimov, A R, et al. (author) Coupled flows and oscillations in asymmetric rotating plasmas 2009 In: PHYSICS OF PLASMAS. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 16:10, s. 102303- Journal article (peer-reviewed)abstract Nonlinear coupling among the radial, axial, and azimuthal flows in an asymmetric cold rotating plasma is considered nonperturbatively. Exact solutions describing an expanding or contracting plasma with oscillations are then obtained. It is shown that despite the flow asymmetry the energy in the radial and axial flow components can be transferred to the azimuthal component but not the vice versa, and that flow oscillations need not be accompanied by density oscillations. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3247875]
22.	Karimov, A. R., et al. (author) Expansion of a cold non-neutral plasma slab 2014 In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 21, s. 122304- Journal article (peer-reviewed)abstract Expansion of the ion and electron fronts of a cold non-neutral plasma slab with a quasi-neutral core bounded by layers containing only ions is investigated analytically and exact solutions are obtained. It is found that on average, the plasma expansion time scales linearly with the initial inverse ion plasma frequency as well as the degree of charge imbalance, and no expansion occurs if the cold plasma slab is stationary and overall neutral. However, in both cases, there can exist prominent oscillations on the electron front.
23.	Karimov, A. R., et al. (author) The processes of nonequilibrium exchange in rotating plasma flows 2016 In: II CONFERENCE ON PLASMA & LASER RESEARCH AND TECHNOLOGIES. - : IOP Publishing. Conference paper (peer-reviewed)abstract The mechanisms of energy/momentum exchange in rotating and compressing plasma flows have been discussed. It has been shown that such flows are capable of transforming the energy of different degrees of freedom into the energy of one degree owing to the interaction of the coupled nonlinear radial, axial and azimuthal electron-ion oscillations. These processes may lead to the additional acceleration of the flow in azimuthal or axial direction so they might be instrumental for the creation of space thrusters employing pulse transformations for propulsion.
24.	Lu, Gaimin, et al. (author) Fully nonlinear electrostatic waves in electron-positron plasmas 2010 In: JOURNAL OF PLASMA PHYSICS. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 76, s. 267-275 Journal article (peer-reviewed)abstract Fully nonlinear electrostatic waves in a plasma containing electrons, positrons, and ions are investigated by solving the governing equations exactly. It is found that both smooth and spiky quasistationary waves exist, and large-amplitude waves necessarily have large-phase velocities, but small-amplitude waves can be both fast and slow.
25.	Marklund, Mattias, et al. (author) New quantum limits in plasmonic devices 2008 In: Europhysics letters. - Les Ulis : EDP Sciences. - 0295-5075 .- 1286-4854. ; 84:1 Journal article (peer-reviewed)abstract Surface plasmon polaritons (SPPs) have recently been recognized as an important future technique for microelectronics. Such SPPs have been studied using classical theory. However, current state-of-the-art experiments are rapidly approaching nanoscales, and quantum effects can then become important. Here we study the properties of quantum SPPs at the interface between an electron quantum plasma and a dielectric material. It is shown that the effect of quantum broadening of the transition layer is most important. In particular, the damping of SPPs does not vanish even in the absence of collisional dissipation, thus posing a fundamental size limit for plasmonic devices. Consequences and applications of our results are pointed out.
26.	Shukla, Nitin, et al. (author) Ion streaming instability in a quantum dusty magnetoplasma 2008 In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 15:1070-664X, s. 044503-1-044503-3 Journal article (peer-reviewed)abstract It is shown that a relative drift between the ions and the charged dust particles in a magnetized quantum dusty plasma can produce an oscillatory instability in a quantum dust acousticlike wave. The threshold and growth rate of the instability are presented. The result may explain the origin of low-frequency electrostatic fluctuations in semiconductors quantum wells. (C) 2008 American Institute of Physics.
27.	Shukla, Nitin, et al. (author) Magnetization of a quantum plasma by photons 2010 In: PHYSICS LETTERS A. - : Elsevier Science B.V., Amsterdam.. - 0375-9601 .- 1873-2429. ; 374:15-16, s. 1749-1750 Journal article (peer-reviewed)abstract It is shown that the ponderomotive force of large-amplitude electromagnetic waves (photons), which includes the electron spin current and exchange potential contributions in a quantum plasma, can generate magnetic fields. The present result can account for the magnetic fields in dense compact astrophysical objects and in the next generation laser-solid density plasma interaction experiments.
28.	Shukla, Nitin, et al. (author) Magnetization of a warm plasma by the nonstationary ponderomotive force of an electromagnetic wave 2009 In: PHYSICAL REVIEW E. - : American Physical Society. - 1539-3755. ; 80, s. 027401- Journal article (peer-reviewed)abstract It is shown that magnetic fields can be generated in a warm plasma by the nonstationary ponderomotive force of a large-amplitude electromagnetic wave. In the present Brief Report, we derive simple and explicit results that can be useful for understanding the origin of the magnetic fields that are produced in intense laser-plasma interaction experiments.
29.	Shukla, Nitin, et al. (author) Nonlinear electromagnetic wave equations for superdense magnetized plasmas 2009 In: PHYSICS OF PLASMAS. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 16:7 Journal article (peer-reviewed)abstract By using the quantum hydrodynamic and Maxwell equations, we derive the generalized nonlinear electron magnetohydrodynamic, the generalized nonlinear Hall-MHD (HMHD), and the generalized nonlinear dust HMHD equations in a self-gravitating dense magnetoplasma. Our nonlinear equations include the self-gravitating, the electromagnetic, the quantum statistical electron pressure, as well as the quantum electron tunneling and electron spin forces. They are useful for investigating a number of wave phenomena including linear and nonlinear electromagnetic waves, as well as three-dimensional electromagnetic wave turbulence spectra and structures arising from mode coupling processes at nanoscales in dense quantum magnetoplasmas.
30.	Shukla, P K, et al. (author) Generation of magnetic fields by the ponderomotive force of electromagnetic waves in dense plasmas 2010 In: JOURNAL OF PLASMA PHYSICS. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 76, s. 25-28 Journal article (peer-reviewed)abstract We show that the non-stationary ponderomotive force of a, large-amplitude electromagnetic move in a very dense quantum plasma wall streaming degenerate electrons can spontaneously create d.c. magnetic fields. The present result can account for the seed magnetic fields in compact astrophysical objects and in the next-generation intense laser-solid density, plasma interaction experiments.
31.	Shukla, P K, et al. (author) Potential distribution around a charged dust grain in an electronegative plasma 2010 In: JOURNAL OF PLASMA PHYSICS. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 76, s. 673-676 Journal article (peer-reviewed)abstract The potential distribution around a charged dust grain in an electronegative plasma is obtained by using the appropriate dielectric susceptibilities for the Boltzmann distributed electrons and negative ions, and for the inertial positive ions that are streaming from the bulk plasma into the electronegative plasma sheath. The existence of oscillatory ion wakefields is shown. Positive ions are trapped/focused in the ion wakefields, and subsequently the negative dust particles are attracted to each other, forming ordered dust structures.
32.	Shukla, P.K., et al. (author) Quantum Hall-MHD equations for a non-uniform dense magnetoplasma with electron temperature anisotropy 2008 In: Journal of Plasma Physics. - 0022-3778 .- 1469-7807. ; 74:05, s. 575-579 Journal article (other academic/artistic)abstract Nonlinear quantum Hall-MHD equations for a warm dense magnetoplasma with an anisotropic electron pressure are derived. The nonlinear equations include the quantum force associated with electron tunneling effects. The newly found equations can be used to investigate the dense plasma stability, as well as different types of waves, instabilities, and nonlinear structures in a warm dense magnetoplasma.
33.	Shukla, Padma, et al. (author) Letter: Dark and grey electromagnetic electron-cyclotron envelope solitons in an electron-positron magnetoplasma 2009 In: Journal of Plasma Physics. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 75:5, s. 575-580 Journal article (other academic/artistic)abstract We present an investigation of the amplitude modulation of an external magnetic field-aligned right-hand circularly polarized electromagnetic electron-cyclotron (EMEC) wave in a strongly magnetized electron-positron plasma. It is shown that the dynamics of the modulated EMEC wave packet is governed by a cubic nonlinear Schrödinger equation. The latter reveals that a modulated wave packet can propagate in the form of either a dark or a grey envelope soliton. This result could have relevance to the transport of electromagnetic wave energy over long distances via envelope solitons in the magnetospheres of pulsars and magnetars.
34.	Shukla, Padma, et al. (author) Wake field generation and nonlinear evolution in a magnetized electron-positron-ion plasma 2008 In: Physics of Plasmas. - New York : AIP Publishing. - 1070-664X .- 1089-7674. ; 15:8, s. 082305-1-082305-4 Journal article (peer-reviewed)abstract The nonlinear propagation of a circularly polarized electromagnetic (CPEM) wave in a strongly magnetized electron-positron-ion plasma is investigated. Two coupled equations describing the interaction between a high-frequency CPEM wave and the low-frequency electrostatic wake field are derived. It is found that the generation of the wake fields partly depends on the presence of the ion species and the external magnetic field. The wake field generation in turn leads to deceleration and frequency down conversion of the electromagnetic pulse.
35.	Shvartsburg, Alexander, et al. (author) Superluminal tunneling of microwaves in smoothly varying transmission lines 2008 In: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - New York : American Physical Society through the American Institute of Physics. - 1063-651X .- 1095-3787. ; 78, s. 016601-1-016601-6 Journal article (peer-reviewed)abstract Tunneling of microwaves through a smooth barrier in a transmission line is considered. In contrast to standard wave barriers, we study the case where the dielectric permittivity is positive, and the barrier is caused by the inhomogeneous dielectric profile. It is found that reflectionless, superluminal tunneling can take place for waves with a finite spectral width. The consequences of these findings are discussed, and an experimental setup testing our predictions is proposed.
36.	Stenflo, Lennart, et al. (author) Collisional contribution to stimulated scattering in plasmas 2014 In: Physics Letters A. - : Elsevier. - 0375-9601 .- 1873-2429. ; 378:5-6, s. 549-550 Journal article (peer-reviewed)abstract The influence of collisions on stimulated Brillouin scattering in magnetized plasmas is discussed. It is shown that new effects occur when the magnitude of the electron quiver velocity exceeds the electron thermal velocity.
37.	Stenflo, Lennart, et al. (author) Large amplitude circularly polarized waves in quantum plasmas 2010 In: JOURNAL OF PLASMA PHYSICS. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 76, s. 261-265 Journal article (peer-reviewed)abstract Some previous dispersion relations for large amplitude waves in plasmas are generalized so that also quantum effects are included.
38.	Stenflo, Lennart, et al. (author) Nonlinear acoustic-gravity waves 2009 In: JOURNAL OF PLASMA PHYSICS. - 0022-3778 .- 1469-7807. ; 75, s. 841-847 Research review (peer-reviewed)abstract Previous results on nonlinear acoustic-gravity waves are reconsidered. It turns out that the mathematical techniques used are somewhat similar to those already adopted by the plasma physics community. Consequently, a future interaction between physicists On different fields, e.g in meteorology and plasma physics, can be very fruitful.
39.	Stenflo, Lennart, 1939-, et al. (author) On the parametric decay of a circularly polarized wave 2011 In: Journal of Plasma Physics. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 77:4, s. 431-435 Journal article (peer-reviewed)abstract The nonlinear decay of a circularly polarized wave is reconsidered. We deduce an explicit expression for the growth rate, and present it in a form which is significantly simpler than those of previous papers.
40.	Stenflo, Lennart, 1939-, et al. (author) Parametric decay of whistler waves in electron magnetohydrodynamics 2011 In: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 83:3, s. 035503-035503 Journal article (peer-reviewed)abstract The nonlinear interaction between three whistler waves is reconsidered. We argue that the squared growth rate of parametric decay instability has to be expressed in a form that is always positive.
41.	Stenflo, Lennart, et al. (author) Rogue waves in the atmosphere 2010 In: JOURNAL OF PLASMA PHYSICS. - : Cambridge University Press. - 0022-3778 .- 1469-7807. ; 76, s. 293-295 Journal article (peer-reviewed)abstract The appearance of rogue waves is well known in oceanographics, optics, and cold matter systems. Here we show a possibility for the existence of atmospheric rogue waves.
42.	Stenflo, Lennart (author) Rysslands Vetenskapsakademi 2009. - 1 In: Thule. - Umeå : Kungl. Skytteanska samfundet. - 978 91 86438 36 4 - 9789186438364 ; , s. 11-18 Book chapter (other academic/artistic)
43.	Stenflo, Lennart, et al. (author) Temperature effects on large amplitude electron plasma oscillations 2016 In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 23:7 Journal article (peer-reviewed)abstract We present a very simple model equation that can describe one-dimensional large amplitude electron plasma oscillations. Published by AIP Publishing.
44.	Anderson, D., et al. (author) Collapse of optical vacuum pulses due to QED nonlinearities 2002 In: Nonlinear Guided Waves and Their Applications, 1–4 September 2002, Stresa, Italy. - : Optics Info Base, Optical Society of America. - 1557527237 Conference paper (other academic/artistic)abstract Due to quantum electrodynamical (QED) effects there are nonlinear corrections to Maxwell's equations in vacuum. We show that stationary two-dimensional light bullets can form, which are unstable and exhibit, the possibility of self-focusing collapse.
45.	Baikov, I. V., et al. (author) Radiation of a neutrino mechanism for type II supernovae 2007 In: Astronomy Reports. ; 51, s. 274- Journal article (peer-reviewed)
46.	Bingham, Robert, et al. (author) Solar coronal heating by plasma waves 2010 In: Journal of Plasma Physics. - : Cambridge university. - 0022-3778 .- 1469-7807. ; 76:2, s. 135-158 Journal article (peer-reviewed)abstract The solar coronal plasma is maintained at temperatures of millions of degrees, much hotter than the photosphere, which is at a temperature of just 6000 K. In this paper, the plasma particle heating based on the kinetic theory of wave–particle interactions involving kinetic Alfvén waves and lower-hybrid drift modes is presented. The solar coronal plasma is collisionless and therefore the heating must rely on turbulent wave heating models, such as lower-hybrid drift models at reconnection sites or the kinetic Alfvén waves. These turbulent wave modes are created by a variety of instabilities driven from below. The transition region at altitudes of about 2000 km is an important boundary chromosphere, since it separates the collision-dominated photosphere/chromosphere and the collisionless corona. The collisionless plasma of the corona is ideal for supporting kinetic wave–plasma interactions. Wave–particle interactions lead to anisotropic non-Maxwellian plasma distribution functions, which may be investigated by using spectral analysis procedures being developed at the present time.
47.	Brodin, Gert, et al. (author) A new decay channel for compressional Alfven waves in plasmas 2008 In: Journal of Plasma Physics. - 0022-3778 .- 1469-7807. ; 74:1, s. 99-105 Journal article (peer-reviewed)abstract We present a new efficient wave decay channel involving nonlinear interactions between a compressional Alfv´en wave, a kinetic Alfv´en wave, and a modified ion sound wave in a magnetized plasma. It is found that the wave coupling strength of the ideal magnetohydrodynamic (MHD) theory is much increased when the effects due to the Hall current are included in a Hall–MHD description of wave–wave interactions. In particular, with a compressional Alfv´en pump wave well described by the ideal MHD theory, we find that the growth rate is very high when the decay products have wavelengths of the order of the ion thermal gyroradius or shorter, in which case they must be described by the Hall–MHD equations. The significance of our results to the heating of space and laboratory plasmas as well as for the Solar corona and interstellar media are highlighted.
48.	Brodin, Gert, et al. (author) Anomalous reflection and excitation of surface waves in metamaterials 2007 In: Physics Letters A. - : Elsevier BV. - 0375-9601 .- 1873-2429. ; 367:3, s. 233-236 Journal article (peer-reviewed)abstract We consider reflection of electromagnetic waves from layered structures with various dielectric and magnetic properties, including metamaterials. Assuming periodic variations in the permittivity, we find that the reflection is in general anomalous. In particular, we note that the specular reflection vanishes and that the incident energy is totally reflected in the backward direction, when the conditions for resonant excitation of leaking surface waves are fulfilled.
49.	Brodin, Gert, et al. (author) Dispersion relation for electromagnetic wave propagation in a strongly magnetized plasma 2006 In: New Journal of Physics. - Bristol, UK : Institute of Physics Pub.. - 1367-2630. ; 8:January, s. 16- Journal article (peer-reviewed)abstract A dispersion relation for electromagnetic wave propagation in a strongly magnetized cold plasma is deduced, taking photon–photon scattering into account. It is shown that the combined plasma and quantum electrodynamic effect is important for understanding the mode-structures in magnetar and pulsar atmospheres. The implications of our results are discussed.
50.	Brodin, Gert, et al. (author) Kinetic and quantum electrodynamical theory for circularly polarized waves in a plasma 2007 In: Physics Letters A. - : Elsevier. - 0375-9601 .- 1873-2429. ; 371, s. 462- Journal article (peer-reviewed)abstract The theory for large amplitude circularly polarized waves propagating along an external magnetic field is further developed. Relativistic effects, quantum electrodynamical effects due to vacuum polarization and magnetization, as well as kinetic effects are included in our formalism. A general dispersion relation, which unites previous results, is derived. As a specific example, a low-frequency kinetic mode with a detailed dependence on the electron distribution function is studied.

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