Pre-Critical Fluctuations in Heavy Fermions

Itinerant antiferromagnetic order can gradually be suppressed by mismatching the nesting of the Fermi surfaces and a quantum critical point is obtained as TN → 0. Within a renormalization group approach we study the instabilities to spin- and charge-density waves and superconductivity, the low-T specific heat and the magnetic susceptibility. All quantities increase on a logarithmic scale when T is lowered, similar to the non-Fermi-liquid behavior observed in some heavy fermion compounds. (author)