The Study of Capillary Discharge Ne-Like 46.9 nm Laser with a 3.5 mm Inner Diameter Capillary

This paper reports the realization of the capillary discharge Ne-like Ar 46.9 nm soft X-ray with a 3.5 mm inner diameter capillary by a 12.6 kA main pulse current. It is the first time that 3.5 mm inner diameter capillary has been used in experiment. In terms of temporal characteristics, the duration (FWHM) of the laser is 1.2 ns, and the laser output pressure range and optimum pressure are 13 - 24 Pa and 17.2 Pa. In terms of spatial characteristics, the laser spots are significantly different with the different Ar pressures, which can be Gaussian-like, annular, annular with a central peak and double-annular. The peak-to-peak divergence angle of the outer annulus at the optimum pressure is 4.6 mrad. The experimental results show that the inner diameter of the capillary has a significant impact on the state of the plasma, influencing both the intensity and the spot of the output laser.