Properties of vapor-deposited and solution-processed targets for laser-driven inertial confinement fusion experiments

Matter and Radiation at Extremes - Tập 3 - Trang 312-321 - 2018
D.R. Harding1,2, M.J. Bonino1, W. Sweet3, M. Schoff3, A. Greenwood3, N. Satoh4, M. Takagi5, A. Nikroo6
1Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, NY 14623-1299, USA
2Department of Chemical Engineering, University of Rochester, Rochester, NY 14623-1299, USA
3General Atomics, 3550 General Atomics Court, San Diego, CA 92121-1122, USA
4Industrial Development Center, Central Research Laboratory, Hamamatsu Photonics K.K., Hamamatsu City, Shizuoka Pref., 431-1202, Japan
5Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871, Japan
6Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94550, USA

Tóm tắt

Targets for low-adiabat direct-drive-implosion experiments on OMEGA must meet rigorous specifications and tight tolerances on the diameter, wall thickness, wall-thickness uniformity, and presence of surface features. Of these, restrictions on the size and number of defects (bumps and depressions) on the surface are the most challenging. The properties of targets that are made using vapor-deposition and solution-based microencapsulation techniques are reviewed. Targets were characterized using confocal microscopy, bright- and dark-field microscopy, atomic force microscopy, electron microscopy, and interferometry. Each technique has merits and limitations, and a combination of these techniques is necessary to adequately characterize a target. The main limitation with the glow-discharge polymerization (GDP) method for making targets is that it produces hundreds of domes with a lateral dimension of 0.7–2 μm. Polishing these targets reduces the size of some but not all domes, but it adds scratches and grooves to the surface. Solution-made polystyrene shells lack the dome features of GDP targets but have hundreds of submicrometer-size voids throughout the wall of the target; a few of these voids can be as large as ∼12 μm at the surface.

Tài liệu tham khảo

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Matter and Radiation at Extremes

Tập 3

312-321

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