Grüneisen divergence near the structural quantum phase transition in ScF₃

ABSTRACT

The cubic perovskite ScF${}_3$ exhibits pronounced isotropic negative thermal expansion and a structural quantum phase transition. We present measurements of the thermal expansion from 200 K to about 1.6 K. We find evidence for stress effects at both high and low temperatures. The coefficient of volumetric thermal expansion and the Grüneisen parameter exhibit power-law temperature dependences above 12 K. The Grüneisen parameter changes sign near 2.4 K and reaches $+160$ by 1.6 K. Our results are consistent with predictions of Grüneisen divergence on the ordered side of a quantum critical point.

KEYWORDS:

• Thermal expansion
• quantum criticality
• quantum critical point
• Grüneisen parameter
• Grüneisen divergence

Acknowledgments

We thank A. Grockowiak and J. C. Cooley for calling our attention to ScF${}_3$ and for helpful discussions, we also thank S. L. Bud'ko and P. C. Canfield for helpful discussions.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

T. Besara http://orcid.org/0000-0002-2143-2254

Additional information

Funding

Work at Occidental College is supported by the National Science Foundation under DMR-1408598. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-1157490 and the State of Florida.