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Thermopower of CexR1-xB6 (R=La, Pr and Nd)

M. S. Kim·Y. Nakai·H. Tou·M. Sera·F. Iga·T. Takabatake·S. Kunii
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Abstract

The thermopower, S, of CexR1-xB6 (R=La, Pr, Nd) was investigated. S with a positive sign shows a typical behavior observed in the Ce Kondo system, an increase with decreasing temperature at high temperatures and a maximum at low temperatures. The S values of all the systems at high temperatures are roughly linearly dependent on the Ce concentration, indicating the conservation of the single-impurity character of the Kondo effect in a wide x range. However, the maximum value of S, S_max, and the temperature, T_max, at which S_max is observed exhibit different x dependences between CexLa1-xB6 and CexR1-xB6 (R=Pr, Nd). In CexLa1-xB6, T_max, which is ~8 K in CeB6, decreases with decreasing x and converges to ~1 K in a very dilute alloy and S_max shows an increase below x ~ 0.1 after decreasing with decreasing x. In CexR1-xB6 (R=Pr, Nd), T_max shows a weak x dependence but S_max shows a roughly linear decrease in x. These results are discussed from the standpoint of the chemical pressure effect and the Ce-Ce interaction. S in the long-range ordered phase shows very different behavior between CexPr1-xB6 and CexNd1-xB6.

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M. S. Kim, Y. Nakai, H. Tou, M. Sera, F. Iga, T. Takabatake, S. Kunii. 2006-04-25. Thermopower of CexR1-xB6 (R=La, Pr and Nd). https://doi.org/10.1143/jpsj.75.064704

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