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Generalized Kadowaki-Woods Relation in Heavy Fermion Systems with Orbital Degeneracy

Hiroshi Kontani
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Abstract

We present a theoretical study of the Kadowaki-Woods relation in the orbitally degenerate periodic Anderson model. Based on Fermi liquid theory, we derive the generalized Kadowaki-Woods relation in the strong coupling limit, $Aγ^{-2} \approx 10^{-5} N(N-1)/2$ [μΩcm(mol K/mJ)^2], where $A$ is the coefficient of the $T^2$ term in the resistivity, $γ$ is the $T$-linear specific heat coefficient, and $N$ is the $f$-orbital degeneracy. This result naturally explains the remarkably smaller value of $Aγ^{-2}$ in various orbitally degenerate (mainly Yb-based) heavy Fermion systems, reported by Tsujii et al.: J. Phys. Cond. Mat. 15 (2003) 1993.

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Hiroshi Kontani. 2003-12-09. Generalized Kadowaki-Woods Relation in Heavy Fermion Systems with Orbital Degeneracy. https://doi.org/10.1143/jpsj.73.515

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