Mechanism for the non-Fermi-liquid behavior in CeCu_6-xAu_x

We propose an explanation for the recently observed non-Fermi-liquid behavior of metallic alloys CeCu6-xAux: Near x = 0.1, the specific heat C is proportional to T ln(T-0/T), and the resistivity increases linearly with temperature T over a wide range of T. These features follow from a model in which three-dimensional conduction electrons are coupled to two-dimensional critical ferromagnetic fluctuations near the quantum critical point x(c) = 0.1. This picture is motivated by the neutron scattering data in the ordered phase (x = 0.2) and is consistent with the observed phase diagram.