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Universality in heavy-fermion systems with general degeneracy

N. Tsujii·H. Kontani·K. Yoshimura
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Abstract

We discuss the relation between the T^{2}-coefficient of electrical resistivity $A$ and the T-linear specific-heat coefficient $γ$ for heavy-fermion systems with general $N$, where $N$ is the degeneracy of quasi-particles. A set of experimental data reveals that the Kadowaki-Woods relation; $A/γ^{2} = 1*10^{-5} {μΩ}(K mol/mJ)^{2}$, collapses remarkably for large-N systems, although this relation has been regarded to be commonly applicable to the Fermi-liquids. Instead, based on the Fermi-liquid theory we propose a new relation; $\tilde{A}/\tildeγ^2=1\times10^{-5}$ with $\tilde{A} = A/(1/2)N(N-1)$ and $\tildeγ = γ/(1/2)N(N-1)$. This new relation exhibits an excellent agreement with the data for whole the range of degenerate heavy-fermions.

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N. Tsujii, H. Kontani, K. Yoshimura. 2005-01-11. Universality in heavy-fermion systems with general degeneracy. https://doi.org/10.1103/physrevlett.94.057201

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