Heavy-fermion alloys at a magnetic instability

Recent experiments on heavy-fermion alloys where remarkable deviations from Fermi-liquid behavior have been observed, will be reviewed. We focus on CeCu6-xAux and related alloys which have been studied most thoroughly. Non-Fermi-liquid behavior, i.e. unusual temperature dependencies of the specific heat, magnetic susceptibility, and electrical resistivity is found at the critical concentration where a transition occurs from a nonmagnetic ground state (i.e. CeCu6) to a magnetically ordered state (x > 0.1). This transition can also be tuned by external pressure, but not by an applied magnetic field.