Testing diamond strength at high pressure

We present two designs to measure the strength of diamond, natural or synthetic, above 30 Mbar. Both designs are based on the Rayleigh–Taylor instability carried out on a laser system providing a truncated ignition pulse. The first is an indentation technique which can be challenging to diagnose because of the low-Z value of carbon. The second is similar to that used in DAC (diamond anvil cell) experiments with a flat diamond squeezing a highly perturbed gold foil and provides the required high-Z diagnostics. Based on two-dimensional hydrocode simulations we conclude that the second technique is superior because of its sensitivity to diamond strength coupled with the benefit of diagnostics at these extremely high pressures.

►We propose an experiment to measure the strength of diamond at pressures > 30 Mb. ► Two designs are proposed based on the Rayleigh–Taylor (RT) instability. ► Both designs use a truncated laser pulse on the National Ignition Facility.