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In this work we report the successful implementation of plasma mirror (PM) technology on an LFEX laser facility at the Institute of Laser Engineering, Osaka University. The LFEX laser pulse was successfully refocused at the target chamber center (TCC) by means of a spherical plasma mirror, resulting in 5  ×  1018 W cm−2 laser intensity, with 45% reflectivity at a laser flux of about 90 J cm−2 on the PM. Experimental results show stable focusing and pointing of the LFEX pulse after PM refocusing. The contrast improvement was demonstrated by both cooler fast electron slope temperature distribution as well as by the ability to shoot sub-µm plastic foils obtaining proton beams with maximum energy exceeding 20 MeV. Experimental results are qualitatively reproduced by 2D particle in cell simulations. [ABSTRACT FROM AUTHOR]

We present the conceptual design of an experimental laser fusion plant known as the laser inertial fusion test (LIFT) reactor. The conceptual design aims at technically connecting a single-shot experiment and a commercial power plant. The LIFT reactor is designed on a three-phase scheme, where each phase has specific goals and the dedicated chambers of each phase are driven by the same laser. Technical issues related to the chamber technology including radiation safety to repeat burst mode operation are discussed in this paper. [ABSTRACT FROM AUTHOR]

We studied the compression and heating of cone-inserted spherical, solid CD shell and DT ice layer targets in strong external magnetic fields using the fast ignition integrated interconnecting simulation system (FI3). The simulation results show that the compression of these spherical targets is stable and that it has the potential to produce a high-areal-density core plasma. In a compressed plasma in an external magnetic field, the magnetic mirror ratio is less than four, which does not reflect the hot electrons needed for core heating. Magnetic beam guiding also significantly enhances the heating efficiency for both CD and DT ice targets. [ABSTRACT FROM AUTHOR]

The compression of an external magnetic field by a laser-driven implosion is studied by using the two-dimensional resistive magneto-radiation hydrodynamic simulation code for electron-beam guiding in fast ignition. The simulation results show that it is possible to compress the magnetic field to 1 kT (107 G); however, the strong magnetic field affects the implosion dynamics because of the suppression of the electron heat flux that crosses the strong magnetic field lines. This result suggests that care must be taken to design a target and the initial conditions for fast ignition with an external magnetic field not only to control the hot electron transport but also to form the high-density plasma. [ABSTRACT FROM AUTHOR]

To enhance the core heating efficiency in electron-driven fast ignition, we propose fast-electron beam guiding using externally applied longitudinal magnetic fields. Based on particle-in-cell simulations for FIREX-class experiments, we demonstrate sufficient beam guiding performance in collisional dense plasma by kilotesla-class external magnetic fields for the case with moderate mirror ratio (⩽10). Boring of the mirror field was found through the formation of magnetic pipe structure due to the resistive effects, which indicates a possibility of beam guiding in high mirror field for higher laser intensity and/or longer pulse duration. [ABSTRACT FROM AUTHOR]