J. Phys. I France 2 (1992) 1853-1860
Spin fluctuation effects on a quasi-2D itinerant electron system : a microscopic model for the marginal Fermi liquidS. Charfi-Kaddour1, R. J. Tarento2 and M. Héritier1
1 Laboratoire de Physique des Solides d'Orsay associé au CNRS, Université de Paris-Sud, 91405 Orsay Cedex, France
2 Laboratoire de Physique des Matériaux, CNRS Bellevue, France
(Received 2 July 1992, accepted in final form 25 July 1992)
We study a model of itinerant two-dimensional electron system exhibiting Van Hove and nesting singularities of the Fermi surface at half-filling of the band. We consider the spin fluctuation electron-electron scattering as the dominant scattering mechanism. This yields a marginal Fermi liquid behaviour at half-filling and a crossover from a normal Fermi liquid to a marginal one away from half-filling. Density of states, magnetic susceptibility, spin excitation spectrum, resistivity, thermopower and the phase diagram using BCS theory obtained by this simple model are in a qualitative agreement with high superconductors.
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