ausblenden:
Schlagwörter:
Quantum Physics, quant-ph, Physics, Atomic Physics, physics.atom-ph
Zusammenfassung:
The electron dynamics in the classically forbidden region during relativistic
tunnel-ionization process is investigated. The classical forbidden region in
the relativistic regime is identified by defining a gauge invariant total
energy operator. Introducing position dependent energy levels inside the
tunneling barrier, we demonstrate that the relativistic tunnel-ionization can
be well described by a one-dimensional intuitive picture. This picture predicts
that, in contrast to the well-known nonrelativisitic regime, the ionized
electron wave packet in the relativistic regime arises with a momentum shift
along the laser propagation direction. This is compatible with results from a
strong field approximation calculation where the binding potential is assumed
to be zero-range. Further, the tunneling time delay, stemming from Wigner's
definition, is investigated for model configurations of tunneling and compared
with results obtained from the exact propagator. By adapting Wigner's time
delay definition the tunneling time is investigated in the deep-tunneling and
in the near-threshold-tunneling regimes. It is shown that while in the
deep-tunneling regime signatures of the tunneling time delay are not measurable
at remote distance, it is detectable, however, in the latter regime.
