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arXiv · 0902.0352

Unusual Magnetic, Thermal, and Transport Behaviors of Single Crystal EuRh2As2

Yogesh Singh·Y. Lee·B. N. Harmon·D. C. Johnston
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Abstract

An antiferromagnetic transition is observed in single crystal EuRh2As2 at a high temperature T_N = 47 K compared to the ferromagnetic Weiss temperature theta = 12 K. We show that this is, surprisingly, consistent with mean field theory. A first-order field-induced magnetic transition is observed at T < T_N with an unusual temperature dependence of the transition field. A dramatic magnetic field-induced reduction of the electronic specific heat coefficient at 1.8-5.0 K by 38% at 9 T is observed. In addition, a strong positive magnetoresistance and a large change in the Hall coefficient occur below 25 K. Band structure calculations indicate that the Fermi energy lies on a steep edge of a narrow peak in the density of states.

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Yogesh Singh, Y. Lee, B. N. Harmon, D. C. Johnston. 2009-02-02. Unusual Magnetic, Thermal, and Transport Behaviors of Single Crystal EuRh2As2. https://doi.org/10.1103/physrevb.79.220401

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