In two newly published articles in Nature Physics, LLE Assistant Scientist Varchas Gopalaswamy and recent graduate Connor Williams ('23 PhD), now a staff scientist at Sandia National Laboratories, share their results from recent experiments on the OMEGA Laser System that demonstrate the potential for a simplified and more-efficient method of designing future "direct-drive" method for generating fusion energy.
The direct-laser illumination of a target capsule differs from the "indirect-drive" method used by scientists at Lawrence Livermore National Laboratory's National Ignition Facility (NIF) in their December 2022 ignition breakthrough experiment, in which laser-induced x rays were used to irradiate a capsule, trigger its implosion, and achieve a net energy gain.
"A major factor contributing to the success of these recent [OMEGA] experiments is the development of a novel implosion design method based on statistical predictions and validated by machine-learning algorithms," says LLE chief scientist Riccardo Betti. Gopalaswamy and Williams used these predictive models to scale up OMEGA results to demonstrate the potential of "direct-drive" inertial confinement fusion on larger and more-powerful megajoule-class lasers like the NIF—an important step on the path toward viable fusion energy.
More information:
Gopalaswamy, V., Williams, C.A., Betti, R. et al. Demonstration of a hydrodynamically equivalent burning plasma in direct-drive inertial confinement fusion. Nat. Phys. (2024). https://doi.org/10.1038/s41567-023-02361-4
Williams, C.A., Betti, R., Gopalaswamy, V. et al. Demonstration of hot-spot fuel gain exceeding unity in direct-drive inertial confinement fusion implosions. Nat. Phys. (2024). https://doi.org/10.1038/s41567-023-02363-2