Ultrafast laser matter interactions: modeling approaches, challenges, and prospects

Abstract

The irradiation of the target surface by an ultrafast femtosecond (fs) laser pulse produces the extreme nonequilibrium states of matter and subsequent phase transformations. Computational modeling and simulation is a very important tool for gaining insight into the physics processes that govern the laser-matter interactions, and, specifically, for quantitative understanding the laser light absorption, electronion energy exchange, spallation, melting, warm dense matter regime, vaporization, and expansion of plasma plume. High-fidelity predictive modeling of a variety of these multi-physics processes that take place at various time and length scales is extremely difficult, requiring the coupled multi-physics and multi-scale models. This topical review covers progress and advances in developing the modeling approaches and performing the state-of-the-art simulations of fs laser-pulse interactions with solids and plasmas. A complete kinetic description of a plasma based on the most accurate Vlasov-Maxwell set of equations is first presented and discussed in detail. After that an exact kinetic model that encompasses the microscopic motions of all the individual particles, their charge and current densities, generated electric and magnetic fields, and the effects of these field on the motion of charged particles in a plasma is briefly reviewed. The methodology of kinetic particle-in-cell (PIC) approach that is well suitable for computational studies of the non-linear processes in laser-plasma interactions is then presented. The hydrodynamic models used for the description of plasmas under the assumption of a local thermodynamic equilibrium include the two-fluid and two-temperature model and its simplifications. The two-temperature model coupled with molecular dynamics (MD) method is finally discussed. Examples are illustrated from research areas such as applications of the fully kinetic, PIC, hydrodynamic, and MD models to studies of ultrafast laser-matter interactions. Challenges and prospects in the development of computational models and their applications to the modeling of ultrafast intense laser-solid and laser-plasma interactions are overviewed.

Magnetization reversal of ferromagnetic nanosample by circularly polarized radiation pulse under resonance condition

“…The interaction of a strong laser field with the electrons of nanosized ferromagnetic samples has recently attracted significant interest due to the new physics and to possible application of the phenomena caused by this interaction [1,2]. The magnetization reversal of nanosized ferromagnetic samples is one of the processes that has been studied experimentally and theoretically in the last decade.…”

Mechanisms of laser-based synthesis and modifications of nanomaterials

“…To better understand the mechanisms involved in laser-based synthesis and modifications of nanomaterials, computer simulations were used in addition to numerous experiments. Several numerical approaches were developed describing the involved multi-scale effects and ranging from ab initio methods, such as DFT and TD-DFT, molecular dynamics (quantum and classical), mesoscopic models, thermal models, thermo-mechanical and hydrodynamical models, etc 2 . By using such approaches, many mechanisms involved were described in detail ranging from optical parameter modifications, structural defects formation, other photo-thermal, photo-chemical, photo-mechanical effects that occur at relatively low laser energies, to much more violent ablative behavior involving material spallation, overheating, explosive boiling, cavitation, and/or dynamic fragmentation 3 .…”