Universality in heavy-fermion systems with general degeneracy

Abstract

We discuss the relation between the T^{2}-coefficient of electrical resistivity $A$ and the T-linear specific-heat coefficient ${\hat{I}}^3$ 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 ${\tilde{\hat{I}}}^3={\hat{I}}^3/(1/2)N(N-1)$. This new relation exhibits an excellent agreement with the data for whole the range of degenerate heavy-fermions.

2 figures, to appear in Phys. Rev. Lett