Structural Competitiveness in Ramp-Compressed Sodium

ORAL  · Invited

Abstract

At high-energy-density conditions, a new realm of quantum behavior emerges including electron localization, structural complexity, core-electron chemistry, and more. Sodium (Na) behaves particularly bizarre at these conditions because of its very high compressibility. Normally a shiny ideal metal, Na transforms to a topological insulator at 200 GPa. This topologically insulating phase (hP4) is due to the valence electrons occupying interstitial positions of its crystalline lattice rather than the orbitals centered on ionic cores. Using lasers as high-pressure drivers, we report the structural and electronic properties of Na at the most extreme compressions yet studied. X-ray diffraction measurements to 480 GPa and 2000 K reveal unexpected new phases. Simultaneous reflectivity measurements suggest a dramatic drop in the conductivity of both the solid and fluid phases. These data together with ab initio evolutionary structure searches reveal a rich structural competitiveness than extends to greater than 300 GPa and thousands of degrees Kelvin. Recent experiments on ramp-compressed sodium at the National Ignition Facility will be discussed.

*This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0003856, the U.S. Department of Energy, Office of Science, Fusion Energy Sciences funding the award entitled High Energy Density Quantum Matter under Award Number DE-SC0020340, the University of Rochester, and the New York State Energy Research and Development Authority. Partial funding for this research is provided by the Center for Matter at Atomic Pressures (CMAP), a National Science Foundation (NSF) Physics Frontiers Center, under Award PHY-2020249.

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Publication: Polsin, Danae N., Amy Lazicki, Xuchen Gong, Stephen J. Burns, Federica Coppari, Linda E. Hansen, Brian J. Henderson et al. "Structural complexity in ramp-compressed sodium to 480 GPa." Nature communications 13, no. 1 (2022): 2534.

Presenters

  • Danae Polsin

    • Laboratory for Laser Energetics

Authors

  • Danae Polsin

    • Laboratory for Laser Energetics

  • Amy E Lazicki

    • Lawrence Livermore Natl Lab

  • Xuchen Gong

    • Lab for Laser Energetics

  • Stephen J Burns

    • University of Rochester

  • F. Coppari

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Lab

  • Linda E Hansen

    • Sandia National Laboratories

  • Brian Henderson

    • University of Rochester

  • Margaret F Huff

    • Lab for Laser Energetics

  • Malcolm I McMahon

    • The University of Edinburgh

  • Marius Millot

    • LLNL
    • Lawrence Livermore National Lab

  • Reetam Paul

    • Lawrence Livermore National Laboratory

  • Raymond F Smith

    • Lawrence Livermore Natl Lab

  • Jon H Eggert

    • Lawrence Livermore Natl Lab
    • LLNL
    • Lawrence Livermore National Lab

  • Gilbert W Collins

    • University of Rochester

  • J. Ryan Rygg

    • University of Rochester