is a high-power 12-beam neodymium
-doped glass laser
at the Osaka University
's Institute for Laser Engineering (大阪大学レーザーエネルギー学研究センター) completed in 1983, which is used for high energy density physics and inertial confinement fusion
research. The name refers to the twelve individual beamlines used to amplify the laser energy.
Unlike most other modern ICF lasers which are frequency tripled
to the third harmonic, the GEKKO XII is only frequency doubled to 532 nm (green light). Compared to most Nd:glass laser ICF experiments GEKKO is also quite small, with beamlines about 10 m long. The 12 beams of the GEKKO laser are capable of delivering about 10 kilojoules per 1-2 ns pulse (10-20 terawatts).
In 1996-1997 the GEKKO system was upgraded with a ~0.4 kJ, 0.5 PW ultra-short pulse beam which was used to investigate a promising new technique of ICF known as "fast ignition", where the compression phase of target implosion is decoupled from the heating phase. GEKKO, using the petawatt beam for heating, along with the original beams for compression, demonstrated a fusion yield enhancement of 3 orders of magnitude when the petawatt beam was used.Nuclear fusion: Fast heating scalable to laser fusion ignition
, Kodama et al., Nature 2002
GEKKO is currently being upgraded with the addition of a second "side-by-side" laser, the LFEX