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Raman free-electron laser with longitudinal electrostatic wiggler and annular electron beam

Journal paper
B. Maraghechi and N. Sepehri Javan
Physics of Plasmas 8, 4193(2001)

A linear theory for the parametric instability of a free-electron laser with a longitudinal electrostatic wiggler is presented. A space-charge wave and a predominantly transverse magnetic wave guide mode are excited when a relativistic electron beam is passed through a static spatially periodic longitudinal electric wiggler. The thick annular electron beam is contained in a cylindrical metal wave guide and an axial magnetic field of arbitrary magnitude. An expression for the wave-field components is derived and solved numerically along with the dispersion relations for the eigenmodes of a wave guide containing a magnetized annular electron beam. Effects of the variation of the beam radii, the axial magnetic field, and electron beam kinetic energy on the growth rate, efficiency, radiation wavelength, and the required pump wavelength are studied. A suitable range of parameters for the generation of millimeter wave is indicated.

Collective Cherenkov effect and anomalous Doppler effect in a bounded spatial region

Journal paper
I. N. Kartashov, M. V. Kuzelev , A. A. Rukhadze , N. Sepehri Javan
Technical Physics 50, 23 (2005)

The problem of the development of instability in a bounded spatial region due to the collective Cherenkov effect or the anomalous Doppler effect is studied in the linear approximation. Threshold conditions for the onset of the convective and absolute instabilities of different longitudinal modes and their growth rates are determined with allowance for reflections from the boundaries of the system. The dynamics of the development of an initial perturbation during convective instability is simulated.

Unsteady processes during stimulated emission from a relativistic electron beam in a quasi-longitudinal electrostatic pump field

Journal paper
I. N. Kartashov , M. V. Kuzelev , N. Sepehri Javan
Plasma Physics Reports 31, 252 (2005)

The problem of stimulated emission from a relativistic electron beam in an external electrostatic pump field is studied. A set of nonlinear time-dependent equations for the spatiotemporal dynamics of the undulator radiation amplitude and the amplitude of the beam space charge field is derived. The beam electrons are described by a modified version of the macroparticle method. The regimes of the single-particle and collective Cherenkov effects during convective and absolute instabilities are considered. The nonlinear dynamics of radiation pulses emitted during the instabilities of the beam in its interaction with the forward and backward electromagnetic waves is investigated.

Absolute radiative instabilities of a relativistic electron beam of the electrostatic field in a resonator with output of the radiation

Journal paper
I. N. Kartashov, M. V. Kuzelev, N. Sepehri Javan
Russian Journal of Applied Physics 3, 59 (2005)

Numerical Simulation of the Instability of a Nonuniform Plasma Flow: Nonlinear Dynamics of Slipping Instability

Journal paper
M. V. Kuzelev and N. Sepehri Javan
Plasma Physics Reports 33, 672 (2007)

Lasing conditions of a free electron laser with helical wiggler

Journal paper
N. Sepehri Javan
Physics of Plasmas 16, 123109 (2009)

Free electron laser with bunched relativistic electron beam and longitudinal electrostatic wiggler

Journal paper
N. Sepehri Javan
Physics of Plasmas 17, 063105 (2010)

Self-focusing of circularly polarized laser pulse in the hot magnetized plasma in the quasi-neutral limit

Journal paper
N. Sepehri Javan and Zh. Nasirzadeh
Physics of Plasmas 19, 112304 (2012)

Modulation instability of an intense laser beam in the hot magnetized electron positron plasma in the quasi neutral limit

Journal paper
N. Sepehri Javan
Physics of Plasmas 19, 122107 (2012)

Threshold conditions for lasing of a free electron laser oscillator with longitudinal electrostatic wiggler

Journal paper
N. Sepehri Javan
Physics of Plasmas 19, 122306 (2012)

Competition of circularly polarized laser modes in the modulation instability of hot magnetoplasma

Journal paper
N. Sepehri Javan
Physics of Plasmas 20, 012120 (2013)

Relativistic nonlinear dynamics of an intense laser beam propagating in the hot electron-positron magnetoactive plasma

Journal paper
N. Sepehri Javan and F. Adli
Physics of Plasmas 20, 062301 (2013)

Polarization effect on the relativistic nonlinear dynamics of an intense laser beam propagating in a hot magnetoactive plasm

Journal paper
N. Sepehri Javan and F. Adli
Physical Review E 88, 043102 (2013)

Optoelectroincs and Advanced Materials Rapid Communications

Journal paper
N. S. Javan, Y. Azizian-kalandaragh, A. Khodayari
Optoelectroincs and Advanced Materials Rapid Communications 7, 639 (2013)

Polarization effect on the Raman backscattering of electromagnetic wave propagating through an electron-positron-ion magnetoplasma

Journal paper
N. Sepehri Javan , B. Maraghechi , R. Nemati Siahmazgi
Physica Scripta 88, 065502 (2013)

Electromagnetically induced transparency of two intense circularly-polarized lasers in cold plasma: Beat-wave second harmonic effect

Journal paper
N. Sepehri Javan and L. Akbari
Communications in Theoretical Physics 61, 246 (2014)

Thermal behavior change in the self-focusing of an intense laser beam in a magnetized electron-ion-positron plasma

Journal paper
N. Sepehri Javan and Mina Hosseinpour Azad
Laser and Particle Beams 32, 321 (2014)

Self-focusing of circularly polarized laser pulse propagating through a magnetized non-Maxwellian plasma

Journal paper
N. Sepehri Javan
Physics of Plasmas 12, 103103 (2014)

Nonlinear dispersion and transverse profile of intense electromagnetic waves, propagating through electron positron-ion hot magnetoplasma

Journal paper
N. Sepehri Javan and S. H. H. Homami
Physics of Plasmas 22, 022113 (2015)

Effect of super-thermal ions and electrons on the modulation instability of a circularly polarized laser pulse in magnetized plasma

Journal paper
R. Etemadpour and N. Sepehri Javan
Laser and Particle Beams 33, 265 (2015)

Effect of dynamical non-neutrality on the modulational instability of laser propagating through hot magnetoplasma

Journal paper
N. Sepehri Javan and F. Rouhi Erdi
Physics of Plasmas 22, 0621162015 (2015)

Nonlinear modes of an intense laser beam interacting with a periodic lattice of nanoparticle

Journal paper
N. Sepehri Javan and S. H. H. Homami
Physics of Plasmas 22, 082311 (2015)

Raman parametric excitation effect upon the third harmonic generation by a metallic nanoparticle lattice

Journal paper
N. Sepehri Javan
Applied Physics 118, 073104 (2015)

Self-focusing of an intense laser pulse interacting with a periodic lattice of metallic nanoparticle

Journal paper
N. Sepehri Javan
Physics of Plasmas 22, 093116 (2015)

Nonlinear dynamics of circularly polarized laser pulse propagating in a magnetized plasma with superthermal ions and mixed nonthermal high-energy tail electrons distributions

Journal paper
R. Etemadpour, N. Sepehri Javan , D. Dorranian
Phys. Plasmas 23, 053105 (2016)

Nonlinear dynamics of circularly polarized laser pulse propagating in a magnetized plasma with q-nonextensive velocity distributions

Journal paper
R. Etemadpour, N. Sepehri Javan, D. Dorranian
Contribution to Plasma Physics 56, 938–950 (2016)

Dielectric coats effect on the third harmonic generation by a metallic nanoparticle lattice exposed to intense laser radiation

Journal paper
N. Sepehri Javan, N. Amjadi, H. Mohammadzadeh
Physics of Plasmas 23, 123114 (2016)

Magnetic field effect on the self-focusing of an intense laser pulse interacting with a bulk medium of graphite nanoparticles

Journal paper
N. Sepehri Javan, F. Rouhi Erdi, M. N. Najafi
Physics of Plasmas 24, 052301 (2017)

Negative and positive dust grain effect on the modulation instability of an intense laser propagating in a hot magnetoplasma

Journal paper
N. Sepehri Javan
Journal of Theoretical and Applied Physics 11, pp. 235–241 (2017)

Theoretical study of terahertz generation by the interaction of two laser beams with graphite nanoparticles

Journal paper
N. Sepehri Javan, F. Rouhi Erdi
Journal of Applied Physics 122, 223103 (2017)

Polarization effect on the nonlinear dynamics of linear chain of interactional metallic nanoparticles exposed on a laser beam: Analytical approach

Journal paper
A. Kheirandish, N. Sepehri Javan, H. Mohammadzadeh
Physica Scripta 93, 095802 (2018)

The study of the dynamics of the interaction of intense electromagnetic fields with metallic nanoparticles is a great interest of some applied nonlinear phenomena in nano-optics and plasmonics. These phenomena include harmonics generation, nano-focusing, self-focusing, nonlinear modes and nano-waveguiding. Using a relativistic modified Drude model, we analytically solve the motion equations of conduction electrons of spherical nanoparticles in a linear chain interacting with a linearly-polarized laser propagating perpendicular to the symmetry axis of the chain. The mutual interaction of each particle with two adjacent neighbors has been considered in the dipole-dipole interaction regime. By means of a perturbative approach, the motion equations related to the first, second and third harmonics of electromagnetic fields are solved. Numerical studies are carried out for a linear chain including 10 of 10 nm radius gold nanoparticles. The effect of interparticle separation and laser polarization on the nonlinear dynamics of the system has been investigated. It is shown that the interaction of particles causes a blueshift for the plasmon resonance of the system for the polarization of laser where the electric field is perpendicular to the symmetry axis of the chain. In the parallel case of the laser electric field, plasmon resonance frequency experiences a redshift for the first and third harmonics displacements, whereas it blueshifts for the second harmonics due to the interparticle interactions. Also, the interaction of particles causes a decrease in the amplitude of the conduction electrons at the plasmon resonance region for the perpendicular state of laser polarization and its increase for the parallel state.

Magnetic field effect on Fresnel coefficients of the thin slab of graphite nano-composite

Journal paper
N. Sepehri Javan, F. Rouhi Erdi
Plasmonics, Published Online (2018)

Theoretical study of artificial Kerr effect on the self-focusing of laser in a dissipative suspension of silver nanoparticles

Journal paper
N. Sepehri Javan, R. Naderali, M. Hosseinpour Azad, M. N. Najafi
Physics of Plasmas 25, 082310 (2018)

Theoretical study of dust grains effect upon the self-focusing of an intense laser propagating in a hot magnetoactive plasma, Waves in Random and Complex Media

Journal paper
N. Sepehri Javan
Under Review (2018)

Perturbative approach to the self-focusing of intense X-ray laser beam propagating in thermal quantum plasma

Journal paper
R. Roozedar Mogaddam, N. Sepehri Javan, K. Javidan, H. Mohammadazadeh
Physics of Plasmas 11, 112104 (2018)

Semi-analytical solution for solitary waves in a dissipative suspension of metallic nanoparticles

Journal paper
N. Sepehri Javan, R. Naderali, M. Hosseinpour Azad, M. N. Najafi
Plasmonics, Published Online (2018)

Technical English for Physicists

Book Chapter
Nasser Sepehri Javan and Behzad Sadri
University of Mohaghegh Ardabili Publishing Center, 2017

On the nonlinear non-stationary theory of stimulated radiation of relativistic electron beam by helical magnetostatic pump field

Conferences Paper
N. Sepehri Javan
International Conference for Students and Young Scientists "Lomonosov" , Physics Section, Moscow State University, Moscow, Russia, 11-15 April 2005 (Oral Presentation).

Effect of resonator length on the nonlinear dynamics of absolute beam instability in a bounded region

Conferences Paper
N. Sepehri Javan
International Conference for Students and Young Scientists "Lomonosov" , Physics Section, Moscow State University, Moscow, Russia, 11-15 April 2005(Oral Presentation).

Simulation of Raman backscattering instability in the interaction of two laser beams in plasma

Conferences Paper
N. Sepehri Javan
34th EPS Conference on Plasma Phys. Warsaw, 2 - 6 July 2007(Poster Presentation).

Third harmonic generation in the interaction of intense laser beam with periodic nanoparticles lattice

Conferences Paper
N. Sepehri Javan
Second Iran-Belarus International Conference on Modern Applications of Nanotechnology, Minsk, Belarus 6-8 May 2015 (Oral Presentation).

Second harmonic generation in the interaction of laser with a linear array of metallic nanoprticles

Conferences Paper
N. Sepehri Javan, H. Mohammadzadeh, A. Farhoomand, A. Kheirandish
2016 Elenite, Bulgaria (Oral Presentation)

Novel theoretical approach for terahertz electromagnetic wave generation by interaction of two lasers in a gaseous medium of graphite nanoparticles

Conferences Paper
N. Sepehri Javan, F. Rouhi Erdi
6th International Conference on Nanotechnology (ICN2017), 9-10 February 2017, AUD University (Conference Centre), Dubai, Emirates (Oral Presentation)

Physics of Plasmas

Journal Reviewer
N. Sepehri Javan
Physics of Plasmas, AIP.

Plasma Science and Technology

Journal Reviewer
N. Sepehri Javan
Plasma Science and Technology, IOP.

Iranian Physics Research Journal

Journal Reviewer
N. Sepehri Javan
Iranian Physics Research Journal, Iranian Society of Physics, Iran.

Journal of Theoretical and Applied Physics Research

Journal Reviewer
N. Sepehri Javan
Journal of Theoretical and Applied Physics Research, Springer.

IEEE Transactions on Microwave Theory and Techniques

Journal Reviewer
N. Sepehri Javan
IEEE Transactions on Microwave Theory and Techniques, IEEE.

Waves in Random and Complex Media

Journal Reviewer
N. Sepehri Javan
Waves in Random and Complex Media, Taylor & Francis.

Journal of Modern Research Physics

Journal Reviewer
N. Sepehri Javan
Journal of Modern Research Physics, Kharazmi University, Iran.

International Journal of Optics and Photonics, Iranian Society of Optics and Photonics

Journal Reviewer
N. Sepehri Javan
International Journal of Optics and Photonics, Iranian Society of Optics and Photonics, Iran.