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arXiv · 1512.02200

Temperature - Pressure phase diagram of the cubic Laves phase Au$_2$Pb

K. W. Chen·D. Graf·T. Besara·A. Gallagher·N. Kikugawa·L. Balicas·T. Siegrist·A. Shekhter·R. E. Baumbach
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Abstract

The temperature ($T$) as a function of pressure ($P$) phase diagram is reported for the cubic Laves phase compound Au$_2$Pb, which was recently proposed to support linearly dispersing "topological" bands, together with conventional quadratic bands. At ambient pressure, Au$_2$Pb exhibits several structural phase transitions at $T_1$ $=$ 97 K, $T_2$ $=$ 51 K, and $T_3$ $=$ 40 K with superconductivity below $T_{\rm{c}}$ $=$ 1.2 K. Applied pressure results in a rich phase diagram where $T_1$, $T_2$, and $T_3$ evolve strongly with $P$ and a new phase is stabilized for $P$ $>$ 0.64 GPa that also supports superconductivity below 1.1 K. These observations suggest that Au$_2$Pb is an ideal system in which to investigate the relationship between structural degrees of freedom, band topology, and resulting anomalous behaviors.

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K. W. Chen, D. Graf, T. Besara, A. Gallagher, N. Kikugawa, L. Balicas, T. Siegrist, A. Shekhter, R. E. Baumbach. 2015-12-07. Temperature - Pressure phase diagram of the cubic Laves phase Au$_2$Pb. https://doi.org/10.1103/physrevb.93.045118

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