Universal relationship of the resistivity and specific heat in heavy-Fermion compounds

Abstract It is observed that the ratio, A/γ 2 , has a common value of 1.0 × 10 −5 μωcm (mole K/mJ) 2 for all of the heavy Fermion compounds, where A is the coefficient of the quadratic term in the temperature dependence of the resistivity and γ is the coefficient of the linear term in the temperature dependence of the specific heat. This universal value, which is at least an order of magnitude above that of common d- band metals, is not accounted for by current microscopic theories and strongly indicates that a more unified understanding of the electron scattering mechanism is required for heavy Fermion materials.