Performance comparison of self-focusing with 1053- and 351-nm laser pulses.
Hole boring characteristics of laser beams are studied using two different laser wavelengths in preformed plasmas with overdense regions. We have shown that a whole beam self-focusing is created in plasma with a considerable density scale length using a 1 microm wavelength laser. The whole beam self-focusing of this type could be used for guiding the ultrahigh intense laser pulse to a highly compressed core for studying the feasibility of a fast ignitor. There is a clear difference in the hole-boring characteristics between two laser wavelengths at 1053 and 351 nm, both in the experiment and the simulation. Using the third-harmonic laser, a whole beam self-focusing is never created. The 351-nm laser beam broke up into filaments resulting in plasma jets observed in our interferogram.
Tanaka
K A
KA
Institute of Laser Engineering, Osaka University Yamada-Oka 2-6, Suita, Osaka 565 Japan. katanaka@ile.osaka-u.ac.jp
Hashimoto
H
H
Kodama
R
R
Mima
K
K
Sentoku
Y
Y
Takahashi
K
K