PT Unknown
AU Liu, F
TI Strong field dynamic in laser-induced processes
PY 2024
DI 10.22032/dbt.62666
WP https://www.db-thueringen.de/receive/dbt_mods_00062666
LA en
DE Starkes Feld
AB This thesis focuses on two strong field ultrafast processes: non-sequential double ionization (NSDI) and high-order above-threshold ionization (HATI). Using an improved quantitative rescattering (QRS) model, we investigate the complex electron dynamics involved in these processes. We first investigate the drastic variations in the correlated two-electron momentum distributions (CMDs) during the transition from near-single-cycle to multi-cycle driving laser pulses. Using QRS model, we reproduce the CMDs for the NSDI of argon. We find that the transition from near-single-cycle to multi-cycle driving laser pulses depends strongly on the details of the pulse envelope. In particular, the cross-shaped structure observed in the CMD for near-single-cycle pulses can be traced back to two main factors: the strong backward scattering of the recolliding electron, and the narrow momentum distributions of the tunnel-ionized electrons which stand in contrast to those for long pulses. This contrast also explains why the cross-shaped distributions collapse. Furthermore, since strong-field ionization can induce electron motion in both the continuum and the valence shell of the parent ion, we explore their interplay by studying laser-induced electron diffraction (LIED) patterns arising from interaction with the potentials of two-hole states of the xenon cation. QRS model is used to calculate the corresponding photoelectron momentum distributions for HATI, providing evidence that the spin-orbit dynamics could be detected by LIED. We identified the contribution of these time-evolving hole states to the angular distribution of the rescattered electrons, particularly noting a distinct change along the backward scattering angles. We benchmark numerical results with experiments using ultrabroad and femtosecond laser pulses centered at 3100 nm.
PI Jena
ER