Push a pressure standard
A challenge in understanding systems under extreme conditions is knowing the exact pressure at which the alien behaviors occur. This situation is caused by the lack of an absolute pressure-density relationship of standard pressure standards. Fratanduono et al. conducted a series of dynamic compression observations on platinum and gold to establish a high pressure scale for these metals up to teapascal conditions (see Jeanloz’s Perspective). This work provides a robust calibration when using these standards in high pressure devices such as diamond anvil cells.
Science, abh0364, this issue p. 1063; see also abi8015, p. 1037
New techniques advance the frontier of high pressure physics beyond 1 teapascal, leading to new discoveries and offering rigorous tests for condensed matter theory and advanced numerical methods. However, the ability to absolutely determine the state of the pressure remains difficult and well-calibrated pressure-density reference materials are required. We conducted shock-free dynamic compression experiments at the National Ignition Facility and the Z Machine to obtain near-absolute, high-precision pressure-density equation of state data for gold and platinum. We have derived two pressure standards experimentally constrained to teapascal conditions. Establishing precise experimental determinations of extreme pressures will facilitate better connections between experiments and theory, paving the way for improving our understanding of the material response to these extreme conditions.