Engineering Aspects of Cryogenic Laser-Fusion Targets

Abstract

For efficient burn of the deuterium-tritium fuel contained within a hollow, spherical laser fusion target the fuel core must first be driven to a high density and then subsequently be elevated in temperature to initiate the reaction. To achieve high final fuel densities the internal pressure within the target must be overcome during the implosion. A cryogenic target, one in which the fuel is condensed as a liquid or solid layer on the inner surface of the spherical shell, may overcome the mechanisms [1] which can limit the final density. Fuel initially confined to the wall of the target cannot respond quickly enough upon absorption of energy to fill the interior volume of the target before the target implodes. At a given level of laser power, a cryogenic liquid or solid layer target should compress to a higher fuel density and produce a higher yield than a target containing the same mass of fuel in the gaseous state[2].