Laser Plasma Instability Experiments with KrF Lasers
Abstract
Deleterious effects of laser-plasma instability (LPI) may limit the maximum laser irradiation that can be used for inertial confinement fusion. The short wavelength (248 nm), large bandwidth, and very uniform illumination available with krypton-fluoride (KrF) lasers should increase the maximum usable intensity by suppressing LPI. The concomitant increase in ablation pressure would allow implosion of low aspect ratio pellets to ignition with substantial gain (>20) at much reduced laser energy. The proposed KrF laser based Fusion Test Facility (FTF) would exploit this strategy to achieve significant fusion power (150 MW) with a rep-rate system that has a per pulse laser energy well below 1 megajoule. Measurements of LPI using the Nike KrF laser are presented at and above intensities needed for the FTF (I~2x1015 W/cm2). The results to date indicate that LPI is indeed suppressed. With overlapped beam intensity above the planar, single beam intensity threshold for the two-plasmon decay instability, no evidence of instability was observed via measurements of 3/2 omega(o) and 1/2 omega(o) harmonic emissions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2007
- Accession Number
- ADA480964
Entities
People
- A. N. Mostovych
- B. Afeyan
- C. M. Brown
- J. L. Weaver
- J. Seely
- Junseok Oh
- L. Phillips
- M. Karasik
- U. Feldman
- V. Serlin
- Y. Aglitskiy
Organizations
- United States Naval Research Laboratory