Calibration of ruby (Cr³⁺:Al₂O₃) and Sm²⁺:SrFCl luminescence lines from the melting of mercury: constraints on the initial slopes

ABSTRACT

We have measured the luminescence shifts of the ruby’s R1- and R2-lines and the line of ⁵D₀→⁷F₀ from Sm²⁺:SrFCl corresponding to the melting pressure of mercury that is recommended by the AIRAPT task force as an International Practical Pressure Scale (IPPS). The linear coefficients of the pressure dependence of the R1-, R2-lines, and the luminescence line of Sm²⁺:SrFCl are determined to be 0.3722 ± 0.002, 0.3796 ± 0.002, and 1.123 ± 0.002 nm/GPa, respectively. The results not only put tight constraints on the initial slopes of ruby and Sm²⁺:SrFCl gauges, but also link the luminescence-based pressure gauges to the more fundamental primary piston gauges.

KEYWORDS:

• Pressure calibration
• ruby luminescence
• Sm²⁺:SrFCl luminescence
• mercury melting

Acknowledgement

We thank D. Y. Chung and P. Rossi for providing the mercury sample and transferring it to HPCAT facilities. We thank S. N. Tkachev for the gas-loading of neon, and V. B. Prakapenka for sharing the IntelliCal calibration lamp. S.K. is grateful to S. Ninet (IMPMC) for help in the cell preparation for the fluorescence measurements (Figure S3).

Disclosure statement

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

Additional information

Funding

This work is supported by the Department of Energy (DOE)-NNSA's Office of Experimental Sciences. Use of the COMPRES-GSECARS gas loading system is supported by COMPRES under NSF EAR -1606856 and by GSECARS under NSF grant EAR-1634415 and DOE grant DE-FG02-94ER14466. The Sm²⁺:SrFCl samples came from W. B. Holzapfel (Univ. Paderborn, Germany) via M. Bonello (Paris).