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Non-Fermi Liquid Behaviour in d = 2 Spatial Dimension

A. Ferraz·S. L. Garavelli·T. Saikawa
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Abstract

We consider a local effective model for fermionic low lying excitations in a metal. Introducing a boson auxiliary field and taking into account that the most significant interactions between quasiparticles arise for those which are near a given point on the Fermi surface, we find that the effective boson-fermion interaction is singular for a spatial dimension d=2. We regularize the theory and apply the renormalization group method. As we vary the coupling constant as a function of an energy scale parameter we show that the model undergoes a non-perturbative regime in which the Fermi liquid theory is no longer valid.

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A. Ferraz, S. L. Garavelli, T. Saikawa. 1997-05-07. Non-Fermi Liquid Behaviour in d = 2 Spatial Dimension. https://arxiv.org/abs/cond-mat/9705057

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