No abstract

Dust particles observed in universe as well as in laboratory and technological plasma devices are still under investigation. At low temperature, these particles are strongly negatively charged and are able to form a 2D or 3D coulomb crystal. In this work, our aim was to check the ideal gas law validity for a 2D single-layer dust crystal recently reported in the literature. For this purpose, we have simulated, using the molecular dynamics method, its thermodynamic properties for different values of dust particles number and confinement parameters. The obtained results have allowed us to invalidate the ideal gas behaviour and to propose an effective equation of state which assumes a near zero dust temperature. Furthermore, the value of the calculated sound velocity was found to be in a good agreement with experimental data published elsewhere.

No abstract

No abstract

In this paper, we simulate by the particle-in-cell method (PIC) the mechanisms of femtoseconde (fs) laser interactions with a metallic or semiconductor target. Our aim is to identify the mechanisms that are responsible for surface nanostructure formation when laser fluences are close to the ablation threshold. For this purpose, we use a theoretical approach, which considers the solid as a gas of free electrons in a lattice of immobile ions. As a result, the simulations shown that those nanostructures occur during the first moments of the interaction and are due to the inhomogeneous distribution of the density of the electrons