Plasmas induced by UV laser ablation have been studied and analysed using timeof- flight measurements. A KrF laser beam of 23 ns FWHM time duration was focused into Si and Nb targets with a moderate laser fluence of 2 J/cm2. A suitable theoretical expressions were derived for fitting the recorded ion current under the assumption of a “shifted” Maxwell- Boltzmann velocity distribution. The deconvolution of time resolved ion current signals, taking into account a multi-mode velocity distribution has revealed that the contribution of the different charge states of ions in the plasma induces electric field which accelerate the expanding plasma along the target normal.
Velocity distribution of ions in UV laser induced plasma plumes
LORUSSO, ANTONELLA;NASSISI, Vincenzo;SICILIANO, MARIA VITTORIA
2010-01-01
Abstract
Plasmas induced by UV laser ablation have been studied and analysed using timeof- flight measurements. A KrF laser beam of 23 ns FWHM time duration was focused into Si and Nb targets with a moderate laser fluence of 2 J/cm2. A suitable theoretical expressions were derived for fitting the recorded ion current under the assumption of a “shifted” Maxwell- Boltzmann velocity distribution. The deconvolution of time resolved ion current signals, taking into account a multi-mode velocity distribution has revealed that the contribution of the different charge states of ions in the plasma induces electric field which accelerate the expanding plasma along the target normal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.