Composite chemical vapor deposition diamond anvils for high-pressure/high-temperature experiments

Abstract

Composite diamond anvils have been developed for high-pressure/high-temperature measurements of diamond anvil cells. The anvils are fabricated using single-crystal chemical vapor deposition (CVD) from previously used and/or slightly damaged anvils made of natural or synthetic diamond. These composite anvils can be fabricated to possess optical characteristics at least comparable to conventional diamond anvils, whereas the single-crystal CVD portion is more durable because of its enhanced toughness relative to natural diamond. The viability of such anvils is demonstrated in measurements on hydrogen at megabar pressures and high temperature.

Keywords:

• CVD diamond anvil
• high-pressure–high-temperature
• hydrogen

Acknowledgements

We thank S. Natarajan and M. Somayazulu for critical reading of the manuscript and suggestions. We also express our appreciation to H. Shu and T. Yu for help with laser cutting. This work was supported by DOE/NNSA (CDAC), NSF-EAR, NSF-DMR, the Balzan Foundation, and the Deborah Rose Foundation.