We present results of wavepacket simulations for multiphoton ionization in argon. A single active electron model is applied to estimate the single-electron ionization rates and photoelectron energy distributions for lambda = 390 nm light with intensities up to I = 2 x 10(14) W cm(-2). The multiphoton ionization rates are compared with R-matrix Floquet calculations and found to be in very good agreement. The photoelectron energy distribution is used to study the nature of ionization at the higher intensities. Our results are consistent with recent calculations and experiments which show the imprint of the tunnelling process in the multiphoton regime. For few-cycle intense pulses, we find that the strong modulation of intensity and increased bandwidth leads to dynamic mixing of the 3d and 5s resonances.
|Number of pages||8|
|Journal||Journal of Physics B: Atomic Molecular and Optical Physics|
|Early online date||24 Jun 2009|
|Publication status||Published - 2009|
ASJC Scopus subject areas
- Condensed Matter Physics
- Atomic and Molecular Physics, and Optics