Effect of small focus on electron heating and proton acceleration in ultrarelativistic laser-solid interactions
File(s)PhysRevLett.124.084802.pdf (675.73 KB)
Published version
Author(s)
Type
Journal Article
Abstract
Acceleration of particles from the interaction of ultraintense laser pulses up to
5
×
10
21
W
cm
−
2
with thin foils is investigated experimentally. The electron beam parameters varied with decreasing spot size, not just laser intensity, resulting in reduced temperatures and divergence. In particular, the temperature saturated due to insufficient acceleration length in the tightly focused spot. These dependencies affected the sheath-accelerated protons, which showed poorer spot-size scaling than widely used scaling laws. It is therefore shown that maximizing laser intensity by using very small foci has reducing returns for some applications.
5
×
10
21
W
cm
−
2
with thin foils is investigated experimentally. The electron beam parameters varied with decreasing spot size, not just laser intensity, resulting in reduced temperatures and divergence. In particular, the temperature saturated due to insufficient acceleration length in the tightly focused spot. These dependencies affected the sheath-accelerated protons, which showed poorer spot-size scaling than widely used scaling laws. It is therefore shown that maximizing laser intensity by using very small foci has reducing returns for some applications.
Date Issued
2020-02-26
Date Acceptance
2019-12-18
Citation
Physical Review Letters, 2020, 124 (8), pp.084802 – 1-084802 – 7
ISSN
0031-9007
Publisher
American Physical Society (APS)
Start Page
084802 – 1
End Page
084802 – 7
Journal / Book Title
Physical Review Letters
Volume
124
Issue
8
Copyright Statement
© 2020 The Author(s). Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
License URL
Identifier
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.124.084802
Subjects
General Physics
01 Mathematical Sciences
02 Physical Sciences
09 Engineering
Publication Status
Published online
Article Number
084802
Date Publish Online
2020-02-26