Non-Fermi-liquid behavior and anomalous suppression of Landau damping in layered metals close to ferromagnetism

Abstract

We analyze the low-energy physics of nearly ferromagnetic metals in two spatial dimensions using the functional renormalization group technique. We find a new low-energy fixed point, at which the fermionic (electronlike) excitations are non-Fermi-liquid (zƒ=13/10) and the magnetic fluctuations exhibit an anomalous Landau damping whose rate vanishes as Γq∼|q|3/5 in the low-|q| limit. We discuss this renormalization of the Landau-damping exponent, which is the major novel prediction of our work, and highlight the possible link between that renormalization and neutron-scattering data on UGe2 and related compounds. Implications of our analysis for YFe2Al10 are also discussed.