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Deviation from the Kadowaki-Woods relation in Yb-based intermediate-valent systems

N. Tsujii·K. Yoshimura·K. Kosuge
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Abstract

The T^2 coefficient of electrical resistivity, A, is compared with the electronic specific-heat coefficient, γ, for a number of Yb-based compounds. It is revealed that many systems including YbCuAl, YbInCu4, YbAl3 and YbCu5 show A/γ^2 values close to 0.4*10^{-6} μΩcm(mol K/mJ)^2, which is remarkably smaller than that known as the Kadowaki-Woods relation, A/γ^2 = 1.0*10^{-5} μΩcm(mol K/mJ)^2. Empirically, the compounds with the smaller A/γ^2 values appear to show weak intersite magnetic-correlation and/or to have almost fully-degenerated (J = 5/2 or 7/2) ground states.

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N. Tsujii, K. Yoshimura, K. Kosuge. 2003-02-17. Deviation from the Kadowaki-Woods relation in Yb-based intermediate-valent systems. https://doi.org/10.1088/0953-8984%2F15%2F12%2F316

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