Demonstration of higher contrast in a high intensity double CPA, double saturable absorber laser system

Kiriyama, Hiromitsu; Shimomura, Takuya; Sasao, Hajime*; Nakai, Yoshiki*; Tanoue, Manabu; Kondo, Shuji; Kanazawa, Shuhei; Mori, Michiaki; Fukuda, Yuji; Kando, Masaki; Bulanov, S.*; Nagashima, Keisuke; Kondo, Kiminori; Sugiyama, Akira; Bolton, P.; Miyanaga, Noriaki*

We have developed a femtosecond high intensity laser system, which combines both Ti:sapphire chirped-pulse amplification (CPA) and optical parametric chirped-pulse amplification (OPCPA) techniques, that produces more than 28 J broadband output energy, indicating the potential for achieving peak powers of 600 TW. With a cleaned high-energy seeded OPCPA preamplifier with a saturable absorber as a front-end in the system, for the final compressed pulse we found that the temporal contrast in this system exceeds 10 on the sub-nanosecond timescale before the main femtosecond pulse.