Biomedical subjects

S L Haan

Publications and source records attributed to S L Haan.

3 recordsLinked to original sources

PubMed2006

Variable time lag and backward ejection in full-dimensional analysis of strong-field double ionization.

Ensembles of 400,000 two-electron trajectories in three space dimensions are used with Newtonian equations of motion to track atomic double ionization under very strong laser fields. We report a variable time lag between e-e collision and double ionization, and find that the time lag plays a key role in the emergence directions of the electrons. These are precursors to production of electron momentum distributions showing substantial new agreement with experimental data.

Journal Article↗

PubMed2005

Nonsequential double ionization as a completely classical photoelectric effect.

We introduce a unified and simplified theory of atomic double ionization. Our results show that at high laser intensities (I>/=10(14) W/cm(2)) purely classical correlation is strong enough to account for all of the main features observed in experiments to date.

Journal Article↗

PubMed2002

Slow-down collisions and nonsequential double ionization in classical simulations.

We use classical simulations to analyze the dynamics of nonsequential double-electron short-pulse photoionization. We utilize a microcanonical ensemble of 10(5) two-electron "trajectories," a number large enough to provide large subensembles and even sub-subensembles associated with double ionization. We focus on key events in the final doubly ionized subensemble and back-analyze the subensemble's history, revealing a classical slow-down scenario for nonsequential double ionization. We analyze the dynamics of these slow-down collisions and find that a good phase match between the motions of the electrons can lead to very effective energy transfer, followed by escape over a suppressed barrier.

Journal Article↗