At ambient pressure and zero field, tetragonal CeAuSb2 hosts stripe antiferromagnetic order at TN=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 that likely breaks C4 symmetry, thus signaling nematic order. The temperature-field-pressure phase diagram of CeAuSb2 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 CeAuSb2 akin to iron-based high-temperature superconductors; however, superconductivity, if present, remains to be discovered.
|Original language||English (US)|
|Journal||Physical Review X|
|State||Published - Mar 2020|
Bibliographical noteFunding Information:
Work at Los Alamos was performed under the auspices of the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering. S. S. acknowledges support through the Laboratory Directed Research and Development program. Scanning electron microscope and energy dispersive x-ray measurements were performed at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy Office of Science. Theory work (R. M. F.) was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award No. DE-SC0012336. X. W. is supported by the University of Chicago Materials Research Science and Engineering Center, which is funded by the National Science Foundation under Grant No. DMR-1420709. R. D. d. R. and D. C. acknowledge financial support from the Brazilian agencies CAPES and FAPESP (Grants No. 2018/00823-0 and No. 2018/22883-5).
© 2020 authors. Published by the American Physical Society.