The Importance of Temperature-Dependent Collision Frequency in PIC Simulation on Nanometric Density Evolution of Highly-Collisional Strongly-Coupled Dense Plasmas

Particle-in-Cell (PIC) method is a powerful plasma simulation tool forinvestigating high-intensity femtosecond laser-matter interaction. However, itssimulation capability at high-density plasmas around the Fermi temperature isconsidered to be inadequate due, among others, to the necessity of implementingatomic-scale collisions. Here, we performed a one-dimensional withthree-velocity space (1D3V) PIC simulation that features the realisticcollision frequency around the Fermi temperature and atomic-scale cell size.The results are compared with state-of-the-art experimental results as well aswith hydrodynamic simulation. We found that the PIC simulation is capable ofsimulating the nanoscale dynamics of solid-density plasmas around the Fermitemperature up to ∼2 ps driven by a laser pulse at the moderate intensityof 10^14-15 W/cm^2, by comparing with the state-of-the-artexperimental results. The reliability of the simulation can be further improvedin the future by implementing multi-dimensional kinetics and radiationtransport.