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arXiv · 1511.00356

Anomalous Magnetothermopower in a Metallic Frustrated Antiferromagnet

Stevan Arsenijević·Jong Mok Ok·Peter Robinson·Saman Ghannadzadeh·Mikhail I. Katsnelson·Jun Sung Kim·Nigel E. Hussey
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Abstract

We report the temperature $T$ and magnetic field $H$ dependence of the thermopower $S$ of an itinerant triangular antiferromagnet PdCrO$_2$ in high magnetic fields up to 32 T. In the paramagnetic phase, the zero-field thermopower is positive with a value typical of good metals with a high carrier density. In marked contrast to typical metals, however, $S$ decreases rapidly with increasing magnetic field, approaching zero at the maximum field scale for $T >$ 70 K. We argue here that this profound change in the thermoelectric response derives from the strong interaction of the 4$d$ correlated electrons of the Pd ions with the short-range spin correlations of the Cr$^{3+}$ spins that persist beyond the Néel ordering temperature due to the combined effects of geometrical frustration and low dimensionality.

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Stevan Arsenijević, Jong Mok Ok, Peter Robinson, Saman Ghannadzadeh, Mikhail I. Katsnelson, Jun Sung Kim, Nigel E. Hussey. 2016-02-24. Anomalous Magnetothermopower in a Metallic Frustrated Antiferromagnet. https://doi.org/10.1103/physrevlett.116.087202

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