Researchers from the University of Rostock and Helmholtz-Zentrum Dresden-Rossendorf conducted groundbreaking experiments at the National Ignition Facility (NIF) in Lawrence Livermore National Laboratory, yielding significant findings on pressure-driven ionization in dense matter. Their study, published on May 24 in Nature, reveals new material properties under extreme conditions, which are critical for understanding astrophysical processes and nuclear fusion. Utilizing NIF’s world-class laser capabilities, the team created conditions mimicking those found in dwarf stars by compressing a beryllium shell to extreme temperatures (around two million kelvins) and pressures (up to three billion atmospheres). This research demonstrated that at these high levels of compression, a majority of beryllium’s electrons transitioned to conductive states, and observed weaker elastic scattering, indicating unique electronic behavior.
Understanding pressure-driven ionization is vital for the energy transport mechanisms in stars, which impacts conditions for life on surrounding celestial bodies. The insights gained will further enhance inertial confinement fusion experiments by providing crucial data on ionization’s role in dense plasmas. The team also aims to explore similar extreme conditions using the Helmholtz International Beamline for Extreme Fields at the European XFEL, which could facilitate additional experiments beyond the current capabilities at NIF.
