Order of magnitude increase in laser-target coupling at near-relativistic intensities using compound parabolic concentrators
Abstract
Achieving a high conversion efficiency into relativistic electrons is central to short-pulse laser application and fundamentally relies on creating interaction regions with intensities ~W/cm. Small focal length optics are typically employed to achieve this goal; however, this solution is impractical for large kJ-class systems that are constrained by facility geometry, debris concerns, and component costs. We fielded target-mounted compound parabolic concentrators to overcome these limitations and achieved nearly an order of magnitude increase to the conversion efficiency and more than tripled electron temperature compared to flat targets. Particle-in-cell simulations demonstrate that plasma confinement within the cone and formation of turbulent laser fields that develop from cone wall reflections are responsible for the improved laser-to-target coupling. {These passive target components can be used to improve the coupling efficiency for all high-intensity short-pulse laser applications, particularly at large facilities with long focal length optics.
Keywords
Cite
@article{arxiv.2012.11563,
title = {Order of magnitude increase in laser-target coupling at near-relativistic intensities using compound parabolic concentrators},
author = {Gerald Jackson Williams and Anthony J. Link and Mark William Sherlock and David A. Alessi and Mark W. Bowers and Brad Golick and Matt Hamamoto and Mark R. Hermann and Dan Kalantar and Kai Nicholas LaFortune and Andrew James Mackinnon and Andrew MacPhee and Mario J. -E. Manuel and David Martinez and Michael Mauldin and Lawrence J. Pelz and Matt Prantil and Matthew Quinn and Bruce A. Remington and Ron Sigurdsson and Paul J. Wegner and Kelly Youngblood and Hui Chen},
journal= {arXiv preprint arXiv:2012.11563},
year = {2021}
}
Comments
6 pages, 5 figures