Open AccessIntensity distribution of 69.8 nm laser pumped by capillary discharge
Author(s) -
Yijun Zhao,
Lianbo Li,
Huaiyu Cui,
Shan Jiang,
Tao Liu,
Wenhong Zhang,
Li Wei
Publication year - 2016
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.65.095201
Subject(s) - laser , intensity (physics) , atomic physics , materials science , range (aeronautics) , plasma , beam divergence , optics , divergence (linguistics) , capillary action , electron density , beam (structure) , physics , beam diameter , laser beams , composite material , linguistics , philosophy , quantum mechanics
In this paper, intensity distribution of 69.8 nm soft X-ray laser pumped by capillary discharge is studied theoretically and experimentally. In experiment, a main current of 11.5 kA is chosen to generate the plasma in a 35 cm long capillary filling with Ar at pressures in a range of 14-16 Pa. The intensity distribution is characterized by two different components. There is a big peak in the center of the intensity distribution profile, and its full width at half maximum divergence is about 0.4 mrad. There are also two small off-axis peaks on the either side of the center peak, and the peak-to-peak divergence is about 1.5 mrad. In theory, three different distributions of electron density are used to study the propagation of Ne-like Ar 69.8 nm laser in a cylindrical plasma column. The spatial intensity distribution for the 69.8 nm laser beam is calculated with the geometrical optics approximation. The results show that the center peak, which has such a small divergence, could be attributed to the slight depression of electron density on the axis.