2D lagrangian code "ATLANT-HE" for simulation of laser-plasma interaction with allowance for hot electron generation and transport

Abstract

Hot electrons may significantly influence interaction of ultra short laser pulses with solids. Accurate consideration of resonant absorption of laser energy and hot electrons generation at a critical surface was achieved through the developed physical and mathematical models. 2D ray tracing algorithm has been developed to simulate laser beam refraction and Bremsstrahlung absorption with allowance for non-linear influence of a strong electromagnetic field. Hot electrons transport was considered as a straight-line flows weakening by a friction force calculated in the approximation of the average state of ionization. Developed models were coupled with 2D Lagrangian gas dynamic code "ATLANT" that takes into account non-linear heat transport. The developed program has been applied to simulate irradiations of Al foils by picosecond laser double pulses. Hot electrons transport and heating resulted in thin foil explosions. The transition from exploding foil regime to the ablative one with foil thickening has been simulated and analyzed at various values of laser light intensity.