A. L. Galkin

Dynamics of an electron driven by relativistically intense laser radiation

The dynamics of an electron driven by a relativistically intense laser pulse is analyzed on the basis of the equation of motion with the Lorentz force in the cases of linear and circular polarizations. Laser fields with nonplane phase fronts accelerate electrons in the longitudinal direction. An electron initially at rest is found not to move along figure-eight trajectories for the linear polarization, and not to move along circular trajectories for the circular polarization.

Electrodynamics of electron in a superintense laser field: New principles of diagnostics of relativistic laser intensity

The dynamics and energy spectra of electrons driven by a relativistically intense laser pulse are analyzed. The description is based on the numerical solution of the relativistic Newton’s equation with the Lorentz force generated by a strong focused optical field. After the interaction with it, electrons retain a considerable fraction of the energy of their oscillations during the interaction. The electron postinteraction energy spectrum is calculated. The energies in the spectrum high-energy tail are determined by the laser pulse intensity at the focal spot. An approach to estimating absolute values of the laser pulse intensity based on the measurement of the energy spectra of the electrons is proposed.

Charged particle motion in the field of a short laser pulse of relativistic intensity

The electron motion in the field of the laser radiation of relativistic intensity was analyzed using the Lorentz force. In the laser pulse field, an initially rest electron does not move along trajectories such as “figure eight”. At relativisitic intensities, the electron oscillations in an optical field are significantly anharmonic.

Emission of zeptosecond electromagnetic pulses by an electron driven by a relativistically intense laser field

The radiation emitted by an electron driven by a relativistically intense laser field comprises a set of electromagnetic pulses with complicated spectral structure having durations much shorter than the optical cycle.

Electron acceleration in quasi-stationary electromagnetic fields during the self-channeling of intense light pulses

We theoretically investigate the possibility of electron acceleration during the self-channeled propagation of laser radiation. We consider a new acceleration mechanism associated with the formation of an ion cloud in material (under the ponderomotive force of the laser radiation) that moves together with the laser pulse. We show that the quasi-stationary electric and magnetic fields generated by the moving ion cloud can lead to the acceleration of electrons up to energies of several dozen MeV and to the formation of an electron beam propagating forward coaxially with the laser pulse. The calculated angular distribution of the accelerated electrons is in satisfactory agreement with published experimental results.

Angular scattering diagrams of linearly polarized relativistic-intensity electromagnetic radiation in a plasma

Instability of the propagation of nonlinear nonmonochromatic relativistic-intensity electromagnetic waves in a cold subcritical-density plasma is analyzed in three-dimensional geometry. Angular diagrams of their scattering are presented. The calculations show that forward and backward scattering may occur. The radiation in a specific direction is a set of harmonics, propagating against a continuum background, whose frequencies depend on the angle. Radiation at a specific frequency propagates in a set of scattering cones. The azimuthal cone angles depend on frequency.

Dynamics of an electron in a relativistically intense laser field including radiaion reaction

The dynamics of an electron in a relativistically intense laser pulse field is described with the radiation reaction being taken into account. The study is based on solving the Newton equation with the Lorentz and the radiation reaction forces. Validation is provided for an iteration technique which makes it possible to remove the discrepancies found in the theoretical models of radiation reaction. It is demonstrated that an electron having a high initial velocity and colliding head-on with a laser pulse sheds a considerable part of its kinetic energy due to the radiation reaction. A broadening of the electromagnetic pulse emitted by the electron occurs as a result of the same effect. The findings obtained can be used to experimentally verify the effect of radiation reaction.

Angular distribution of electrons in the field of a short laser pulse of relativistic intensity

Based on the dynamics of the electron in the field of a laser pulse of relativistic intensity, the electron emission angles with respect to the laser pulse propagation axis are calculated. The angular distribution of accelerated electrons is analyzed together with their energy spectrum. It is shown that fast electrons forming the high-energy spectral region are emitted into a fixed angular cone.

Suppression of diffraction overshoots near the edge of a perfectly conducting wedge by rotating the polarization ellipse of an incident wave

The effects of polarization suppression of diffraction spatial intensity variations are studied for a plane electromagnetic wave with elliptical polarization near the edge of a perfectly conducting rectangular wedge.

Diagnostics of the peak laser intensity based on the measurement of energy spectra of electrons accelerated by the laser beam

A new method of the measurement of the maximal laser pulse intensity at the focal spot is suggested. The measurement of the energies of electrons ejected from the focal spot by laser radiation is used.