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arXiv · 1008.4635

Metal-nonmetal transition in LixCoO2 thin film and thermopower enhancement at high Li concentration

Y. Ishida·A. Mizutani·K. Sugiura·H. Ohta·K. Koumoto
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Abstract

We investigate the transport properties of LixCoO2 thin films whose resistivities are nearly an order of magnitude lower than those of the bulk polycrystals. A metal-nonmetal transition occurs at ~0.8 in a biphasic domain, and the Seebeck coefficient (S) is drastically increased at ~140 K (= T*) with increasing the Li concentration to show a peak of magnitude ~120 \muV/K in the S-T curve of x = 0.87. We show that T* corresponds to a crossover temperature in the conduction, most likely reflecting the correlation-induced temperature dependence in the low-energy excitations.

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Y. Ishida, A. Mizutani, K. Sugiura, H. Ohta, K. Koumoto. 2010-08-27. Metal-nonmetal transition in LixCoO2 thin film and thermopower enhancement at high Li concentration. https://doi.org/10.1103/physrevb.82.075325

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