We have performed nonperturbative time-dependent calculations of single and double ionization of atomic calcium by short and intense laser pulses using a two-active electron model (TAE). It is shown that the significant enhancement of the Ca2+ yield observed in a recent experiment  using feedback control techniques originates from the time asymmetry of the pulse shape. The initial part of the pulse prepares a coherent superposition of doubly excited states which is transferred into the double electron continuum at later times. An asymmetric shape, with a slowly decreasing tail, therefore favors the production of Ca2+.
|Original language||English (US)|
|Number of pages||6|
|State||Published - Apr 1 2003|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Industrial and Manufacturing Engineering