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arXiv · 1602.06742

Field-Temperature Phase Diagram and Entropy Landscape of CeAuSb$_2$

Lishan Zhao·Edward A. Yelland·Jan A. N. Bruin·Ilya Sheikin·Paul C. Canfield·Veronika Fritsch·Hideaki Sakai·Andrew P. Mackenzie·Clifford W. Hicks
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Abstract

We report a field-temperature phase diagram and an entropy map for the heavy fermion compound CeAuSb$_2$. CeAuSb$_2$ orders antiferromagnetically below $T_N=6.6$~K, and has two metamagnetic transitions, at 2.8 and 5.6~T. The locations of the critical endpoints of the metamagnetic transitions, which may play a strong role in the putative quantum criticality of CeAuSb$_2$ and related compounds, are identified. The entropy map reveals an apparent entropy balance with Fermi liquid behavior, implying that above the Néel transition the Ce moments are incorporated into the Fermi liquid. High-field data showing that the magnetic behavior is remarkably anisotropic are also reported.

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Lishan Zhao, Edward A. Yelland, Jan A. N. Bruin, Ilya Sheikin, Paul C. Canfield, Veronika Fritsch, Hideaki Sakai, Andrew P. Mackenzie, Clifford W. Hicks. 2016-02-22. Field-Temperature Phase Diagram and Entropy Landscape of CeAuSb$_2$. https://doi.org/10.1103/physrevb.93.195124

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