Hollow microspheres as targets for staged laser-driven proton acceleration
Author
Summary, in English
A coated hollow core microsphere is introduced as a novel target in ultra-intense laser-matter interaction experiments. In particular, it facilitates staged laser-driven proton acceleration by combining conventional target normal sheath acceleration (TNSA), power recycling of hot laterally spreading electrons and staging in a very simple and cheap target geometry. During TNSA of protons from one area of the sphere surface, laterally spreading hot electrons form a charge wave. Due to the spherical geometry, this wave refocuses on the opposite side of the sphere, where an opening has been laser micromachined. This leads to a strong transient charge separation field being set up there, which can post-accelerate those TNSA protons passing through the hole at the right time. Experimentally, the feasibility of using such targets is demonstrated. A redistribution is encountered in the experimental proton energy spectra, as predicted by particle-in-cell simulations and attributed to transient fields set up by oscillating currents on the sphere surface.
Department/s
Publishing year
2011
Language
English
Publication/Series
New Journal of Physics
Volume
13
Document type
Journal article
Publisher
IOP Publishing
Topic
- Atom and Molecular Physics and Optics
Status
Published
ISBN/ISSN/Other
- ISSN: 1367-2630