Proceedings of International Conference on Physics in ... - KEK

which were comparable to those before the main
amplification. The encircled energy was estimated to be
more than 70% at Fλ=2.5 with the observed far-field
patterns when 10% without the DFM correction. In
addition, all shots with kilo-joule pulse energy were
below 10 μrad in the pointing beam stability before the
compressor in fig. 4. The amplified pulse beams go into
Figure 6: Block diagram <strong>of</strong> the “Gekko-EXA” laser.
Figure 7: Arrangement plan <strong>of</strong> the “Gekko-EXA” laser.
the pulse compressor to be arranged with 1 x 4 beams
from 2 x 2. The pulse compressor is our original diamond
trace compressor with four large (91 cm x 42 cm) gratings
for one-beam diffraction, which results in sixteen gratings
for one-beam compression, shown in fig. 5. The obtained
minimum pulse duration is 2.2 ps. The LFEX laser is
gradually moving into the plasma experiments. The laser