Non-thermal laser driven plasma-blocks for proton boron avalanche fusion as direct drive option

Fusion energy from protons reacting with ^(11) B,HB11,is extremely difficult or impossible when using thermal ignition by laser irradiation.This changes radically when using picosecond laser pulses with powers above petawatts dominated by nonlinear force driven ultrahigh ac-celeration of plasma blocks for a non-thermal initiation of igniting solid density HB11 fuel.For a cylindrical trapping of the reaction,laser produced ultrahigh magnetic fields above kiloTesla,have to be combined.The experimentally confirmed highly increased HB11 fusion gains due to avalanche reaction may lead to a scheme of an environmentally clean and economic power reactor.

Heat wave fast ignition in inertial confinement energy

An accelerated micro-foil is used to ignite a pre-compressed cylindrical shell containing deuterium–tritium fuel.The well-known shock wave ignition criterion and a novel criterion based on heat wave ignition are developed in this work.It is shown that for heat ignition very high impact velocities are required.It is suggested that a multi-petawatt laser can accelerate a micro-foil to relativistic velocities in a very short time duration(picosecond)of the laser pulse.The cylindrical geometry suggested here for the fast ignition approach has the advantage of geometrically separating the nanosecond lasers that compress the target from the picosecond laser that accelerates the foil.The present model suggests that nuclear fusion by micro-foil impact ignition could be attained with currently existing technology.

Ultrafast ignition with relativistic shock waves induced by high power lasers

In this paper we consider laser intensities greater than 1016 W cm-2where the ablation pressure is negligible in comparison with the radiation pressure.The radiation pressure is caused by the ponderomotive force acting mainly on the electrons that are separated from the ions to create a double layer(DL).This DL is accelerated into the target,like a piston that pushes the matter in such a way that a shock wave is created.Here we discuss two novel ideas.Firstly,the transition domain between the relativistic and non-relativistic laser-induced shock waves.Our solution is based on relativistic hydrodynamics also for the above transition domain.The relativistic shock wave parameters,such as compression,pressure,shock wave and particle flow velocities,sound velocity and rarefaction wave velocity in the compressed target,and temperature are calculated.Secondly,we would like to use this transition domain for shockwave-induced ultrafast ignition of a pre-compressed target.The laser parameters for these purposes are calculated and the main advantages of this scheme are described.If this scheme is successful a new source of energy in large quantities may become feasible.