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arXiv · 1908.07649

Nematic state in CeAuSb$_{2}$

S. Seo·Xiaoyu Wang·S. M. Thomas·M. C. Rahn·D. Carmo·F. Ronning·E. D. Bauer·R. D. dos Reis·M. Janoschek·J. D. Thompson·R. M. Fernandes·P. F. S. Rosa
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Abstract

At ambient pressure and zero field, tetragonal CeAuSb$_{2}$ hosts stripe antiferromagnetic order at $T_{N} = 6.3$ K. Here we first show via bulk thermodynamic probes and x-ray diffraction measurements that this magnetic order is connected with a structural phase transition to a superstructure which likely breaks $C_{4}$ symmetry, thus signaling nematic order. The temperature-field-pressure phase diagram of CeAuSb$_{2}$ subsequently reveals the emergence of additional ordered states under applied pressure at a multicritical point. Our phenomenological model supports the presence of a vestigial nematic phase in CeAuSb$_{2}$ akin to iron-based high-temperature superconductors; however, superconductivity, if present, remains to be discovered.

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S. Seo, Xiaoyu Wang, S. M. Thomas, M. C. Rahn, D. Carmo, F. Ronning, E. D. Bauer, R. D. dos Reis, M. Janoschek, J. D. Thompson, R. M. Fernandes, P. F. S. Rosa. 2019-08-20. Nematic state in CeAuSb$_{2}$. https://doi.org/10.1103/physrevx.10.011035

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