Leveraging oxide reactive sputtering for thermal insulation in laser-heated diamond anvil cell

ABSTRACT

We have developed an oxide reactive sputtering technique aiming at rapidly sputtering high-quality oxide films on a diamond surface, providing excellent thermal insulation in high-pressure and temperature experiments using a laser-heated diamond anvil cell (LH-DAC). We identified conditions for rapid deposition of an alumina layer on diamond anvils, showing deposition rates as high as 0.67 um/hr. We also investigated the deposition conditions of zirconia, which have lower thermal conductivity than alumina. Laser-heating tests were performed at high pressures and temperatures to evaluate the thermal insulation of the oxide film deposited on the diamond anvils. The heating efficiency of zirconia-deposited anvils was higher than that of the alumina-deposited ones. Our zirconia-sputtered anvils were capable of generating up to 2580 K at around megabar pressure without additional thermal insulation, demonstrating the potential of this technique for ultra-high temperature generation.

KEYWORDS:

• Diamond anvil cell
• sputtering
• high temperature

Acknowledgments

We thank two anonymous reviewers for their helpful comments. We acknowledge Shoh Tagawa for valuable discussion.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the JSPS grants nos. 21H04968 to K.H. and 23K19083 to K.O. XRD measurements were performed at BL10XU, SPring-8 (proposal no. 2023B1322).