Examining laser-plasma keys to fusion energy

Nuclear fusion holds the promise of sustainable, abundant clean energy. Scientists have successfully demonstrated controlled fusion in the laboratory, but have not yet been able to demonstrate useful energy production.

Nuclear fusion must take place in plasma, an ionized medium, and generally requires a combination of density and temperature that is difficult to achieve. As part of a worldwide effort to demonstrate the fast ignition inertial confinement approach to fusion, researchers at The Ohio State University and the Department of Energy’s Jupiter Laser Facility have been examining intense laser-plasma interactions.

“We’ve created numerical models of an intense laser with parameters relevant for fast ignition fusion in a plasma and to determine the resulting distribution of energetic electrons excited and their subsequent propagation,” said Douglass Schumacher, Ph.D., an associate professor of Physics at OSU. “Modeling also has been used to help design some aspects of the experimental program.”

Schumacher’s team has leveraged the computational muscle of the Ohio Supercomputer Center’s Glenn Cluster to model specular reflection of an intense laser from a metallic surface, the divergence angle of a laser-generated hot electron beam, the use of Kα radiation as a diagnostic tool, red-shifting of reflected light due to ponderomotive compression of the plasma density profile and the spectra of escaping electrons when ultrashort laser pulses are employed. The research is helping to determine the conditions where fast ignition might work and to develop better diagnostics for fast ignition studies.

--

Project lead: Douglass W. Schumacher, The Ohio State University

Research title: Modeling intense laser plasma interactions in conjunction with

an experimental program for 2010

Funding source: Department of Energy, The Ohio State University