Nuclear fusion from the explosions of laser driven deuterium clusters

When intense femtosecond lasers irradiate small atomic or molecular clusters. High energy ions are produced from the explosion of these clusters. This phenomenon has recently been exploited to produce DD fusion neutrons in a gas of exploding deuterium clusters (illustrated below). In this experiment, a high intensity, ultrafast laser pulse is focused into a gas of deuterium clusters and rapidly heats them. These clusters subsequently explode, ejecting deuterium ions with energies of many keV. This process creates a plasma filament with a diameter roughly that of the laser focus and a length comparable to the extent of the gas jet plume (~ 1 mm). The fast deuterium ions then collide with ions ejected from other clusters in the plasma. From this experiment it appears that reasonable fusion efficiencies are possible even with lasers of modest energy per pulse. This suggests an intriguing possibility in which a laser-driven neutron source could be used to realize a high-flux neutron facility for a variety of unique materials science experiments of direct relevance to neutron radiation damage studies.		Picture of a cluster fusion plasma. The laser is focused to a point beneath a deuterium gas jet and a white fusion plasma results.
Research in this area is aimed at increasing the fusion yield per laser shot. To do this, the dynamics of the laser depositing of energy in the plasma are studied and novel interaction geometries are explored.

 

UT participants: Kirk Madison (p.-doc) Todd Ditmire (Prof.)

LLNL collaborators: Prav Patel Dwight Price

IC collaborators Roland Smith

GA collaborators: Jason Zweiback Tom Cowan

Here is a review article on this topic: [PDF]

Some interesting papers in this topic from our previous research:

• T. Ditmire, J. Zweiback, V. P. Yanovsky, T. E. Cowan, G. Hays, and K. B. Wharton, "Nuclear Fusion from Explosions of Femtosecond-Laser Heated Deuterium Cluster", Nature, 398, 492 (1999). [PDF]
• T. Ditmire, J. Zweiback, V. P. Yanovsky, T. E. Cowan, G. Hays, and K. B. Wharton, "Studies of Nuclear Fusion in Gases of Deuterium Clusters Heated by a Femtosecond Laser," Phys. Plas. 7, 1993 (2000). [PDF]
• J. Zweiback, T.E. Cowan, J. Hartley, G. Hays, R. Howell R.A. Smith, C. Steinke, and T. Ditmire, "Characterization of Fusion Burn Time in Exploding Deuterium Cluster Plasmas ," Phys. Rev. Lett.,85, 3640 (2000). [PDF]
• J. Zweiback, R.A. Smith, T.E. Cowan, G. Hays, K.B. Wharton, and T. Ditmire, "Nuclear Fusion Driven by Coulomb Explosions of Large Deuterium Clusters," Phys. Rev. Lett. 84, 2634 (2000). [PDF]
• L.J. Perkins, et al. "The Investigation of High Intensity Laser Driven Micro Neutron Sources for Fusion Materials Research at High Fluence" Nuclear Fusion 40, 1 (2000). [PDF]