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Marginal Fermi Liquid Theory in the Hubbard Model

Y. Kakehashi·P. Fulde
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Abstract

We find Marginal Fermi Liquid (MFL) like behavior in the Hubbard model on a square lattice for a range of hole doping and on-site interaction parameter U. Thereby we use a self-consistent projection operator method. It enables us to compute the momentum and frequency dependence of the single-particle excitations with high resolution. The Fermi surface is found to be hole-like in the underdoped and electron-like in the overdoped regime. When a comparison is possible we find consistency with finite temperature quantum Monte Carlo results. We also find a discontinuous change with doping concentration from a MFL to Fermi liquid behavior resulting from a collapse of the lower Hubbard band. This renders Luttinger's theorem inapplicable in the underdoped regime.

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Y. Kakehashi, P. Fulde. 2005-01-10. Marginal Fermi Liquid Theory in the Hubbard Model. https://doi.org/10.1103/physrevlett.94.156401

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