Nuclear Fusion Driven by Coulomb Explosions of Large Deuterium Clusters

report on measurements of fusion yield from these deuterium cluster explosions and show that the fusion yield is strongly related to the size of the deuterium clusters. The rapid increase in fusion yield with increasing cluster size can be attributed to the greater ion energies associated with the Coulomb explosion of the larger clusters and the rapid variation in fusion cross section with ion energy. Although large, high Z clusters typically exhibit a “plasmalike” behavior [6,13] due to the fact that space charge forces confine many of the photoionized electrons to the body of the cluster, we expect that, provided the laser has a fast enough rise time and a high enough ponderomotive potential (Up), D2 clusters can be stripped of almost all their electrons by the laser pulse before the cluster explodes. The rise time of the laser pulse required can be estimated from the time required for a uniformly charged sphere expanding under Coulomb forces to grow to roughly twice its initial radius. For a sphere of ionized deuterons, this time is