The toroidal diamond anvil cell for detailed measurements under extreme static pressures.

The upper pressure achievable in the conventional Diamond Anvil Cell (DAC) had been limited to approximately 400 GPa since the early 2000s. We show that by sculpting the diamond anvil tip into a toroidal shape with a Focussed Ion Beam, the maximum pressure can be extended toward the terapascal pressure range. Measurements similar to standard DACs are so possible in terms of precision, reproducibility, sample dimensions and type of materials from gas to solids and with any atomic number. Our toroidal-DAC design will be compared to other innovative schemes recently proposed to extend the pressure limit of the DAC , such as the double-stage DAC.