Enhanced laser-driven proton acceleration using nanowire targets
Open Access
- 26 January 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in Scientific Reports
- Vol. 11 (1), 1-11
- https://doi.org/10.1038/s41598-020-80392-0
Abstract
Laser-driven proton acceleration is a growing field of interest in the high-power laser community. One of the big challenges related to the most routinely used laser-driven ion acceleration mechanism, Target-Normal Sheath Acceleration (TNSA), is to enhance the laser-to-proton energy transfer such as to maximize the proton kinetic energy and number. A way to achieve this is using nanostructured target surfaces in the laser-matter interaction. In this paper, we show that nanowire structures can increase the maximum proton energy by a factor of two, triple the proton temperature and boost the proton numbers, in a campaign performed on the ultra-high contrast 10 TW laser at the Lund Laser Center (LLC). The optimal nanowire length, generating maximum proton energies around 6 MeV, is around 1–2 $$\upmu$$ m. This nanowire length is sufficient to form well-defined highly-absorptive NW forests and short enough to minimize the energy loss of hot electrons going through the target bulk. Results are further supported by Particle-In-Cell simulations. Systematically analyzing nanowire length, diameter and gap size, we examine the underlying physical mechanisms that are provoking the enhancement of the longitudinal accelerating electric field. The parameter scan analysis shows that optimizing the spatial gap between the nanowires leads to larger enhancement than by the nanowire diameter and length, through increased electron heating.
Funding Information
- Natural Sciences and Engineering Research Council of Canada (RGPIN-2018-05772)
- Vetenskapsrådet
- Knut och Alice Wallenbergs Stiftelse
- LaserLaB Europe (654148)
- Fonds de recherche du Québec – Nature et technologies (174726)
- Canada Foundation for Innovation
- Compute Canada (pve-323-ac)
This publication has 69 references indexed in Scilit:
- Surface-plasmon-enhanced MeV ions from femtosecond laser irradiated, periodically modulated surfacesPhysics of Plasmas, 2012
- Short pulse laser interaction with micro-structured targets: simulations of laser absorption and ion accelerationNew Journal of Physics, 2011
- A model for the efficient coupling between intense lasers and subwavelength grating targetsPhysics of Plasmas, 2008
- Proton Acceleration with High-Intensity Ultrahigh-Contrast Laser PulsesPhysical Review Letters, 2007
- Laser-driven proton scaling laws and new paths towards energy increaseNature Physics, 2005
- Nanostructured surfaces: challenges and frontiers in nanotechnologyJournal of Physics: Condensed Matter, 2004
- Optimization of ion acceleration in the interaction of intense femtosecond laser pulses with ultrathin foilsPhysical Review E, 2003
- Plasma Expansion into a VacuumPhysical Review Letters, 2003
- Intense Picosecond X-Ray Pulses from Laser Plasmas by Use of Nanostructured “Velvet” TargetsPhysical Review Letters, 2000
- Effect of Large Supersymmetric Phases on Higgs ProductionPhysical Review Letters, 2000