Anomalous Magnetothermopower in a Metallic Frustrated Antiferromagnet
Abstract
We report the temperature T and magnetic field H dependence of the thermopower S of an itinerant triangular antiferromagnet PdCrO2 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 Cr3 + spins that persist beyond the Néel ordering temperature due to the combined effects of geometrical frustration and low dimensionality.
- Publication:
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Physical Review Letters
- Pub Date:
- February 2016
- DOI:
- 10.1103/PhysRevLett.116.087202
- arXiv:
- arXiv:1511.00356
- Bibcode:
- 2016PhRvL.116h7202A
- Keywords:
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- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 5 pages and 4 figures in Main text + 4 pages and 5 figures in Supplementary material