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arXiv · 0811.0498

Dual electronic states in thermoelectric cobalt oxide

Patrice Limelette·Sylvie Hebert·Herve Muguerra·Raymond Fresard·Charles Simon
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Abstract

We investigate the low temperature magnetic field dependence of the resistivity in the thermoelectric misfit cobalt oxide [Bi1.7Ca2O4]0.59CoO2 from 60 K down to 3 K. The scaling of the negative magnetoresistance demonstrates a spin dependent transport mechanism due to a strong Hund's coupling. The inferred microscopic description implies dual electronic states which explain the coexistence between localized and itinerant electrons both contributing to the thermopower. By shedding a new light on the electronic states which lead to a high thermopower, this result likely provides a new potential way to optimize the thermoelectric properties.

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Patrice Limelette, Sylvie Hebert, Herve Muguerra, Raymond Fresard, Charles Simon. 2008-11-04. Dual electronic states in thermoelectric cobalt oxide. https://doi.org/10.1103/physrevb.77.235118

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