A spectroscopic study of plasmas produced by laser ablation of hollow aluminium targets

Abstract

In this paper we report the study of plasmas generated when the laser beam hits a target surface in the middle of a hole through the target, the diameter of the hole being slightly smaller than the laser beam's waist. The hole's axis coincides with the laser beam's axis. In such a case two plasma clouds are observed: one expands from the front hole opening towards the laser, the other from the back side of the target in the opposite direction. The experiments indicate that the plasma in front of the target is similar in appearance to the plasma generated by ablation of a planar surface. On the other hand, the plasma behind the target is significantly less dense and is also much colder than the corresponding plasma in front of the target.

A Study of Dynamics of a Head-on Collision between Two Laser-Produced Plasmas

“…The plasma clouds between the two targets were observed side-on with a gated XUV pinhole camera with a gate time of 5 ns or with a XUV flat-field spectrograph [8], [9] with time resolution of 10 ns. Details on the experimental set-up and on the data reduction process are described before [10], [11].…”

Space- and time-resolved soft x-ray emission from laser-produced magnesium plasma

“…But laser ablation is a complicated process in the early stages of ablation <100 ns. Only limited reports have been found for laser-produced plasma diagnostics at delay times less than 100 ns [15,16]. Most of the established diagnostic techniques, such as optical emission spectroscopy, mass spectroscopy, Langmuir probe etc, are not suitable for studying the dynamics of the plasma, especially at the early stages.…”