Development of capillary Z-pinch discharge soft X-ray laser

摘要

The work on lasing in Ne-like Ar at 46.9nm by using a Blumlein transmission line is reported. The discharge system consists of a Marx generator with maximum charging voltage of 300kV, a Blumlein transmission line and a pre-pulse circuit. Both results of theory and experiment illustrate that the inherent high-amplitude pre-pulse (～5kA) causes serious wall ablation, low homogeneity of plasma column and there would be no lasing. While the pre-pulse with an amplitude of ～20A greatly reduces ablation, engenders uniform plasma column, and provides necessary condition for lasing. The soft x-ray amplification in Ne-like Ar at 46.9nm has been achieved. The plasma columns are pumped by a 28～36kA current pulse with 80ns half-cycle duration in a 3.1mm-diametter and 12cm-length capillary channels filled with Ar gas. The full width at half-maximum of the laser spike is determined to be ～2ns and the output energy of the laser is estimated to be 3μJ.