We investigate the short range structure in strongly coupled, fluid-like plasmas using the hypernetted chain approach generalized to multi-component systems. Good agreement with numerical simulations validates this method for the parameters considered. We found strong mutual impact on the spacial arrangement for systems with multiple ion species which were most clearly pronounced in the static structure factor. Quantum pseudo-potentials were used to mimic diffraction and exchange effects in dense electron-ion systems. We demonstrate that the different kinds of pseudo-potentials proposed lead to large differences in both the pair distributions and the structure factors. Large discrepancies were also found in the predicted ion feature of the x-ray scattering signal illustrating the need for comparison with full quantum calculations or experimental verification.

Collisional absorption of dense fully ionized plasmas in strong laser fields is investigated using quantum statistical methods as well as molecular dynamics simulations. For high-frequency fields, quantum statistical expressions for the electrical current density and the electron-ion collision frequency are presented. Strong correlations are taken into account and their influence on the absorption rate is discussed. The expressions are valid for arbitrary field strength assuming the nonrelativistic case. In addition, molecular dynamics simulations were performed to calculate the heating of dense plasmas in laser fields. Comparisons with the analytic results for different plasma parameters are given. There are considered the cases of isothermal plasmas as well as two-temperature plasmas. Furthermore, results for the velocity distribution function under the influence of intense laser fields are presented which show a different behavior in comparison to weak fields.

Collisional absorption of dense, fully ionized plasmas in strong laser fields is investigated starting from a quantum kinetic equation with non-Markovian and field-dependent collision integrals in dynamically screened Born approximation. This allows to find rather general balance equations for the energy and the current. For high-frequency laser fields, quantum statistical expressions for the electrical current density and the cycle-averaged electron-ion collision frequency in terms of the Lindhard dielectric function are derived. The expressions are valid for arbitrary field strength assuming the nonrelativistic case. Numerical results are presented to discuss these quantities as a function of the applied laser field and for different plasma parameters. In particular, nonlinear phenomena such as higher harmonics generation and multiphoton emission and absorption in electron-ion collisions are considered. The significance to include quantum effects is demonstrated comparing our results for the collision frequency with previous results obtained from classical theories.

Optimal control techniques combined with femtosecond laser pulse shaping are applied to steer and enhance the strong-field induced emission of highly charged atomic ions from silver clusters embedded in helium nanodroplets. With light fields shaped in amplitude and phase we observe a substantial increase of the Ag q+ yield for q > 10 when compared to bandwidth-limited and optimally stretched pulses. A remarkably simple double-pulse structure, containing a low-intensity prepulse and a stronger main pulse, turns out to produce the highest atomic charge states up to Ag 20+ . A negative chirp during the main pulse hints at dynamic frequency locking to the cluster plasmon. A numerical optimal control study on pure silver clusters with a nanoplasma model converges to a similar pulse structure and corroborates that the optimal light field adapts to the resonant excitation of cluster surface plasmons for efficient ionization.

The interaction of intense laser fields with silver and argon clusters is investigated theoretically using a modified nanoplasma model. Single pulse and double pulse excitations are considered. The influence of the dense cluster environment on the inner ionization processes is studied including the lowering of the ionization energies. There are considerable changes in the dynamics of the lasercluster interaction. Especially, for silver clusters, the lowering of the ionization energies leads to increased yields of highly charged ions.