41 research outputs found
Mott scattering of polarized electrons in a strong laser field
We present analytical and numerical results of the relativistic calculation
of the transition matrix element and differential cross section for
Mott scattering of initially polarized Dirac particles (electrons) in the
presence of strong laser field with linear polarization. We use exact
Dirac-Volkov wave functions to describe the dressed electrons and the collision
process is treated in the first Born approximation. The influence of the laser
field on the degree of polarization of the scattered electron is reported.Comment: 12 pages, 11 figures, Revte
Spin dynamics of wave packets evolving with the Dirac Hamiltonian in atoms with high Z
The motion of circular WP for one electron in central Coulomb field with high
Z is calculated. The WP is defined in terms of solutions of the Dirac equation
in order to take into account all possible relevant effects in particular the
spin-orbit potential. A time scale is defined within which spin dynamics must
be taken into account mainly in the atoms with high Z. Within this time scale
there exists a mechanism of collapses and revivals of the spin already shown by
the authors for harmonic oscillator potential and called the 'spin-orbit
pendulum'. However this effect has not the exact periodicity of the simpler
model, but the WP's spatial motion is nevertheless quite similar.Comment: 17 pages, 9 figures, LaTeX2e, uses IOP style files (included). Title
changed, one reference adde
On the absence of bound-state stabilization through short ultra-intense fields
We address the question of whether atomic bound states begin to stabilize in
the short ultra-intense field limit. We provide a general theory of ionization
probability and investigate its gauge invariance. For a wide range of
potentials we find an upper and lower bound by non-perturbative methods, which
clearly exclude the possibility that the ultra intense field might have a
stabilizing effect on the atom. For short pulses we find almost complete
ionization as the field strength increases.Comment: 34 pages Late
On the Influence of Pulse Shapes on Ionization Probability
We investigate analytical expressions for the upper and lower bounds for the
ionization probability through ultra-intense shortly pulsed laser radiation. We
take several different pulse shapes into account, including in particular those
with a smooth adiabatic turn-on and turn-off. For all situations for which our
bounds are applicable we do not find any evidence for bound-state
stabilization.Comment: 21 pages LateX, 10 figure
Ionization Probabilities through ultra-intense Fields in the extreme Limit
We continue our investigation concerning the question of whether atomic bound
states begin to stabilize in the ultra-intense field limit. The pulses
considered are essentially arbitrary, but we distinguish between three
situations. First the total classical momentum transfer is non-vanishing,
second not both the total classical momentum transfer and the total classical
displacement are vanishing together with the requirement that the potential has
a finite number of bound states and third both the total classical momentum
transfer and the total classical displacement are vanishing. For the first two
cases we rigorously prove, that the ionization probability tends to one when
the amplitude of the pulse tends to infinity and the pulse shape remains fixed.
In the third case the limit is strictly smaller than one. This case is also
related to the high frequency limit considered by Gavrila et al.Comment: 16 pages LateX, 2 figure
Propagation dynamics in an autoionization medium
Published versio
Breakdown of stabilization of atoms interacting with intense, high-frequency laser pulses
Published versio
Atoms interacting with intense, high-frequency laser pulses: Effect of the magnetic-field component on atomic stabilization
Published versio