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We demonstrate an ion acceleration scheme capable of simultaneously focusing and accelerating a multi- species ion beam with monoenergetic spectra to a few micron radius. The focal length and ion mean energy can be independently controlled: the former by using a different front-surface shape and the latter by tuning the laser- plasma parameters. We interpret the results using simple models and validate the results using first-principles simulations. The scheme is applicable to different laser transverse profiles and multi-ion species targets, and limiting factors for the ion focusing are delineated. The generated ion beam exhibits high charge, low emittance, and high-energy flux and is of interest for various applications, including inertial confinement fusion, high-flux neutron generation, and biomedical applications.
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Centrifugal-electrostatic confinement fusion
A model for plasma confinement is developed and applied for describing an electrically confined thermonuclear plasma. The plasma confinement model includes both an analytical approach that excludes space charge effects and a classical trajectory Monte Carlo simulation that accounts for space charge. The plasma consists of reactant ions that form a non-neutral plasma without electrons. The plasma drifts around a negatively charged electrode. Conditions are predicted for confining a deuterium–tritium plasma using a 460 kV applied electric potential difference. The ion plasma would have a 20 keV temperature, a 1020 m−3 peak density, and a 110 keV average kinetic energy per ion (including drift and thermal portions at a certain point in the plasma). The fusion energy production rate is predicted to be 10 times larger than the energy loss rate, including contributions associated with both plasma loss to electrodes and secondary electron emission. However, an approach for enhancing the fusion power density may have to be employed to realize a practical use for centrifugal-electrostatic confinement fusion.
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- Award ID(s):
- 1803047
- PAR ID:
- 10538207
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Physics of Plasmas
- Volume:
- 30
- Issue:
- 9
- ISSN:
- 1070-664X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1063/5.0161536
