Charge instabilities at the metamagnetic transition

Carsten Honerkamp

Max-Planck-Institut für Festkörperforschung Stuttgart

We investigate instabilities in the charge channel in the vicinity of (meta-)magnetic transitions of itinerant electron systems. Based on a weak coupling analysis we argue that in a one-band t-t' Hubbard model near the van Hove filling and dominant ferromagnetic fluctuations it is difficult to account for a microscopic mechanism for a d-wave Pomeranchuk deformation of the Fermi surface. A similar deformation has been considered for the metamagnetic transition in Sr3Ru2O7 (Grigera et al., Science 306,1154 (2004)). As an alternative we discuss the possibility of charge inhomogeneity on the nano scale. This extends the analogy of the metamagnetic transition to a liquid-gas transition.