Abstract
We demonstrate the fast isochoric heating of an imploded dense plasma using a multi-picosecond kJclass
petawatt laser at the GEKKO-LFEX laser facility at the Institute of Laser Engineering, Osaka
University. We experimentally achieved 2.2 petapascal pressure of an ultra-high-energy-density state
with 4.6 kJ of total laser energy that is one order of magnitude lower than the energy used in the conventional
implosion scheme. These findings clarified that the scheme is an efficient way to create the
petapascal pressure state, which is a unique testbed for fast ignition schemes. In this paper, we describe
the heating mechanism of fast isochoric heating and X-ray measurements using doped targets that can
characterize plasmas above the keV temperature and solid density.
