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Thermal/Electronic Transport Properties and Two-Phase Mixtures in La_{5/8-x}Pr_{x}Ca_{3/8}MnO_{3}

K. H. Kim·M. Uehara·C. Hess·P. A. Sharma·S-W. Cheong
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Abstract

We measured thermal conductivity, k, thermoelectric power, S, and dc electric conductivity, sigma, of La_{5/8-x}Pr_{x}Ca_{3/8}MnO_{3}, showing an intricate interplay between metallic ferromagnetism (FM) and charge ordering (CO) instability. The change of k, S and sigma with temperature (T) and x agrees well with the effective medium theories for binary metal-insulator mixtures. This agreement clearly demonstrates that with the variation of T as well as x, the relative volumes of FM and CO phases drastically change and percolative metal-insulator transition occurs in the mixture of FM and CO domains.

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K. H. Kim, M. Uehara, C. Hess, P. A. Sharma, S-W. Cheong. 2000-03-10. Thermal/Electronic Transport Properties and Two-Phase Mixtures in La_{5/8-x}Pr_{x}Ca_{3/8}MnO_{3}. https://doi.org/10.1103/physrevlett.84.2961

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