D.W. Liu

EFFECTS OF PLASMA SHIELDING ON PULSED LASER ABLATION

We have developed a theoretical model which studies the characteristics of laser-plasma interaction, the effect of plasma shielding and plasma radiation in the ablation process. The model is used to simulate 25 ns square pulsed laser irradiation on YBa2Cu3O7 targets, and pulsed laser with the pulse width of 25 ns (FWHM) irradiation on Ni targets. The evolution of the plasma length and the transmitted intensity are performed. The model shows the variation of ablation depth with energy density. Moreover, we obtain the dependence of the ablation depth on the number of laser pulses. The satisfactorily good agreement between our results and experimental results confirms that plasma shielding plays a relevant role in the ablation process.