Low-frequency wiggler modes in the free-electron laser with a dusty magnetoplasma medium

Abstract

An advanced incremental scheme for generating tunable coherent radiation in a freeelectron laser has been presented: the basic concept is the use of a relativistic electron beam propagating through a magnetized dusty plasma channel where dust helicon, dust Alfven and coupled dust cyclotron-Alfven waves can play a role as a low-frequency wiggler, triggering coherent emissions. The wiggler wavelength at the sub-mm level allows one to reach the wavelength range from a few nm down to a few Å with moderately relativistic electrons of kinetic energies of a few tens/hundreds of MeV. The laser gain and the effects of beam selfelectric and self-magnetic fields on the gain have been estimated and compared with findings of the helical magnetic and electromagnetic wigglers in vacuum. To study the chaotic regions of the electron motion in the dusty plasma wave wiggler, a time independent Hamiltonian has been obtained. The Poincare surface of a section map has been used numerically to analyze the nonintegrable system where chaotic regions in phase-space emerge. This concept opens a path toward a new generation of synchrotron sources based on compact plasma structures.

Non‐linear absorption of an intense laser pulse propagating in wiggler‐assisted underdense collisional plasma

“…here s = ( e ∕ e ) 1 2 is the sound velocity. By employing the above dimensionless parameters, Equations (21), (22), and (23) are rewritten in the following form, e e0 = exp…”

“…The propagation of intense laser pulse in plasma leads to numerous instabilities and non‐linear effects including, Raman and Brillouin instabilities, modulational and filamentational instabilities, laser self‐focusing, and self‐modulation properties . Furthermore, these processes play a significant role in advanced physical events such as, laser fusion, X‐ray lasers, laser ablation, inertial confinement fusion (ICF), and optical harmonic generation . In the laser‐plasma interaction, the fraction of laser absorption during interaction between ultrashort, ultra‐intense laser pulses and dense plasma is a significant problem of ion acceleration, high energy density matter production, and fast ignition .…”

Chaotic dynamics in X-ray free-electron lasers with an optical undulator

“…In recent years, XFELs have been designed to generate radiation starting from the shot noise of a relativistic electron beam, the so-called self-amplified spontaneous emission (SASE) mechanism 7 , 8 . However, the main drawbacks of SASE-XFELs are relatively poor longitudinal coherence and a long conventional magnetostatic undulator is required 9 , 10 . Moreover, to realize SASE-XFELs at angstrom wavelengths, extremely high brilliance e-beam, and beam energies of order GeV are required 11 , 12 .…”

Quantum regime of a plasma-wave-pumped free-electron laser in the presence of an axial magnetic field

“…The plasma can significantly slow down the radiation mode thereby relaxing the beam energy and beam quality requirements considerably (Jafarinia et al, 2013). The presence of plasma enables the possibility of employing the plasma modes as wigglers which have a very short period for the excitation of shorter wavelengths (Jafari, 2015). The effective wiggler wavelength in a plasma wiggler is w = 2c=!…”