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Origin of the large thermoelectric power in oxygen-variable RBaCo_{2}O_{5+x} (R=Gd, Nd)

A. A. Taskin·A. N. Lavrov·Yoichi Ando
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Abstract

Thermoelectric properties of GdBaCo_{2}O_{5+x} and NdBaCo_{2}O_{5+x} single crystals have been studied upon continuous doping of CoO_2 planes with either electrons or holes. The thermoelectric response and the resistivity behavior reveal a hopping character of the transport in both compounds, providing the basis for understanding the recently found remarkable divergence of the Seebeck coefficient at x=0.5. The doping dependence of the thermoelectric power evinces that the configurational entropy of charge carriers, enhanced by their spin and orbital degeneracy, plays a key role in the origin of the large thermoelectric response in these correlated oxides.

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A. A. Taskin, A. N. Lavrov, Yoichi Ando. 2006-02-27. Origin of the large thermoelectric power in oxygen-variable RBaCo_{2}O_{5+x} (R=Gd, Nd). https://doi.org/10.1103/physrevb.73.121101

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