Hajime OKADA^*, Hiromitsu KIRIYAMA, Michiaki MORI, Yoshiki NAKAI, Takuya SHIMOMURA, Manabu TANOUE, Shuji KONDO, Shuhei KANAZAWA, Hiroyuki DAIDO, Toyoaki KIMURA, and Toshiki TAJIMA

Advanced Photon Research Center, Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215, Japan

(Received September 1, 2008; Accepted December 2, 2008)

We have demonstrated highly efficient broadband amplification by an optical parametric chirped pulse amplifier (OPCPA) system that uses high energy seed pulses. The OPCPA consists of three type I B-barium borate (BBO) crystals pumped by a Q-switched Nd:YAG laser. We successfully amplified the microjoule level seed pulses to 78 mJ with a pump-to-signal optical conversion efficiency of 26% at a 10 Hz repetition rate. To our knowledge these results represent the most optically efficient OPCPA to date pumped by a typical Q-switched laser.

Key words: solid-state laser, OPCPA, ultra-short pulse, spectral shaping

^*E-mail address: okada.hajime@jaea.go.jp