A feasibility of a new approach of laser fusion in plasma without implosion has been proposed and discussed using an intense laser. The cross-section of nuclear reaction is increased by the enhanced penetrability of nuclei through the Coulomb barrier. In this approach, an intense laser field of more than 10 EW was required to distort the Coulomb barrier to obtain enough penetrability. In the new improved model, a nuclear potential with meson attractive force is considered. Enhancement is observed for penetrability around EW or less power laser due to a nuclear potential. Energy gain even with Deuterium-Deuterium reaction can be obtained on this scheme in Deuterium plasma with energetic nucleon theoretically.

Recent progress in research on Light Ion Beams-Inertial Confinement Fusion (LIB-ICF) at ILE, Osaka University is summarized. We report on pulsed power compression using PEOS, a super high voltage source, on diode physics, on beam trajectory control for focusing, on beam-target interactions and on a conceptual reactor design (Rokko I) in this article.

Light ion beams for the energy drive for inertial confinement fusion (ICF) research have been studied on a super high voltage generation system (SHVS) using an inductive voltage adder system. A simple analysis implied the capability of the output voltage of several tens of MV. This system has a feasibility of acceleration of ions heavier than proton. The two-stage charge stripping ion diode is considered a SHVS diode. This diode reduces the size of the induction adder module and extends the possible power range in operation. We have constructed a prototype SHVS, which consists of eight stages of induction cavities (4MV, 40kA, 100ns) powered by a Reiden IV pulse power machine. The first ion diode experiments on the induction adder were performed with the beam extraction type ion diode (Br applied magnetic field). The injection plasma ion source was used to control the diode impedance and then the diode voltage. The time delay of ion current turn-on was reduced from 15–20 ns to less than 5 ns by this ion source.

Inertial Confinement Fusion (ICF) research has been extensively advanced with the increase of the focusable power on target by the development of glass laser technology and its higher harmonic generation (Yamanaka & Kato et al. 1981) and by CO2 lasers (Yamanaka & Nakai et al. 1981) which cover the wavelength range from 10 μm to 0·25 μm and power densities up to 1017 W/cm2. With improved understanding of the implosion in the fuel pellet, breakeven conditions, or ignition, are expected to be achieved within the 1980's with the construction of lasers in the region of 100 kJ and 100 TW output power.

An approach to an alternative laser fusion in a magnetic field with an intense laser of exa watt level will be discussed. Such a strong field in an exa watt laser will induce enhanced nuclear tunneling through the propagation in plasma. This causes an enhanced nuclear reaction for fusion. We discuss the possibilities to apply this to nuclear fusion energy and to obtain break even in a 100 kJ laser.

An approach to produce efficient and economical hydrogen, which is one of the solutions of future energy, by inertial fusion energy reactor is discussed. This fusion reactor is with magnetic field such as mirror machine and graphite solid blanket. Neutrons and charged particles from nuclear reactions are separated from each other by this magnetic field. This results in hydrogen production efficiently in a solid blanket of high temperature with a breakeven of electricity by direct conversion of charged particle. The output of hydrogen may meet not only economical issue but also ecological issues.