A study of laser albation near the critical point

Abstract

Laser ablation is arguably the most important application areas of pulsed lasers, and is also the foundation of many other applications, such as precision microfabrication and pulsed laser deposition. However, underlying physical phenomena are still far from completely understood because ablation occurs at extremely high temperatures and pressures. In this study, the author investigates laser material interaction with emphasis on how a material behaves near the critical point. Employing temperature-dependent material property models and the Redlich-Kwong equation of state, the critical point behavior of materials under laser irradiation is studied at least qualitatively and some interesting results are obtained regarding the change in ablation modes in the thermal regime and the role of critical point.