Title :
Prepulse-free petawatt laser for a fast ignitor
Author :
Kitagawa, Yoneyoshi ; Fujita, Hisanori ; Kodama, Ryosuke ; Yoshida, Hidetsugu ; Matsuo, Satoshi ; Jitsuno, Takahisa ; Kawasaki, Tetsuji ; Kitamura, Hisao ; Kanabe, Tadashi ; Sakabe, Shuji ; Shigemori, Keisuke ; Miyanaga, Noriaki ; Izawa, Yasukazu
Author_Institution :
Inst. of Laser Eng., Osaka Univ., Japan
fDate :
3/1/2004 12:00:00 AM
Abstract :
We have developed a prepulse-free short-pulse Nd:glass laser system of 0.9-PW peak power to heat a pre-imploded high-density plasma. An optical parametric chirped amplification system is introduced to reduce the prepulses to an amplitude (1.5×10-8) of that of the main pulse. The compressor is a double-path grating pair system 94 cm in diameter compressing the 50-cm-diameter laser beam to 470 fs. An off-axis parabolic mirror has focused the 420-J energy to an intensity of 2.5×1019 W·cm-2. Part of the front end of the chirped pulse is seeded into the preamplifier of the GEKKO XII laser, used to implode a pellet target, to enable the petawatt laser to irradiate the pre-imploded pellet during stagnation of a few tens of picoseconds.
Keywords :
chirp modulation; explosions; laser beams; laser fusion; mirrors; optical focusing; optical parametric amplifiers; optical pulse compression; optical pulse generation; plasma heating by laser; solid lasers; 0.9 PW; 420 J; 470 fs; 50 cm; 94 cm; Gekko XII laser; Nd:glass laser system; SiO2:Nd; chirped pulse; compressor; double-path grating pair; fast ignitor; high-density plasma; laser beam diameter; off-axis parabolic mirror; optical parametric chirped amplification system; preimploded pellet; prepulse-free petawatt laser; Chirp; Gratings; Laser beams; Mirrors; Nonlinear optics; Optical pulses; Plasmas; Power lasers; Pulse amplifiers; Stimulated emission;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2003.823043
