Homogeneous, Micron-Scale High-Energy-Density Matter Generated by Relativistic Laser-Solid Interactions

N F Beier; H Allison; P Efthimion; K A Flippo; L Gao; S B Hansen; K Hill; R Hollinger; M Logantha; Y Musthafa; R Nedbailo; V Senthilkumaran; R Shepherd; V N Shlyaptsev; H Song; S Wang; F Dollar; J J Rocca; A E Hussein

doi:10.1103/PhysRevLett.129.135001

Homogeneous, Micron-Scale High-Energy-Density Matter Generated by Relativistic Laser-Solid Interactions

Phys Rev Lett. 2022 Sep 23;129(13):135001. doi: 10.1103/PhysRevLett.129.135001.

Authors

N F Beier^{1

2}, H Allison², P Efthimion³, K A Flippo⁴, L Gao³, S B Hansen⁵, K Hill³, R Hollinger⁶, M Logantha², Y Musthafa², R Nedbailo⁶, V Senthilkumaran¹, R Shepherd⁷, V N Shlyaptsev⁶, H Song⁶, S Wang⁶, F Dollar², J J Rocca^{6

8}, A E Hussein¹

Affiliations

¹ Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2R3, Canada.
² STROBE, NSF Science and Technology Center, University of California, Irvine, California 92617, USA.
³ Princeton Plasma Physics Laboratory, Princeton, New Jersey 08536, USA.
⁴ Los Alamos National Laboratory, P.O. Box 1163, Los Alamos, New Mexico 87545, USA.
⁵ Sandia National Laboratories, Albuquerque, New Mexico 87185, USA.
⁶ Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80521, USA.
⁷ Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
⁸ Department of Physics, Colorado State University, Fort Collins, Colorado 80521, USA.

PMID: 36206410
DOI: 10.1103/PhysRevLett.129.135001

Abstract

Short-pulse, laser-solid interactions provide a unique platform for studying complex high-energy-density matter. We present the first demonstration of solid-density, micron-scale keV plasmas uniformly heated by a high-contrast, 400 nm wavelength laser at intensities up to 2×10^{21} W/cm^{2}. High-resolution spectral analysis of x-ray emission reveals uniform heating up to 3.0 keV over 1 μm depths. Particle-in-cell simulations indicate the production of a uniformly heated keV plasma to depths of 2 μm. The significant bulk heating and presence of highly ionized ions deep within the target are attributed to the few MeV hot electrons that become trapped and undergo refluxing within the target sheath fields. These conditions enabled the differentiation of atomic physics models of ionization potential depression in high-energy-density environments.