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arXiv · 1002.3032

A two-step density-matrix renormalization-group study of coupled Luttinger liquids

S. Moukouri·E. Eidelstein
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Abstract

We report a two-step density-matrix renormalization-group computation of the equal-time single-particle Green's function, the density-density correlations, and the low-frequency spectral weight function of a spinless fermion model in an anisotropic two-dimensional lattice at half-filling. We find that at weak couplings the density-density correlations have the universal decay of a Fermi liquid; the spectral weight function displays a sharp quasi-particle peak. But in the vicinity of a quantum critical point, these correlations strongly deviate from a Fermi liquid prediction and a pseudogap opens in the spectral weight function.

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S. Moukouri, E. Eidelstein. 2010-09-03. A two-step density-matrix renormalization-group study of coupled Luttinger liquids. https://doi.org/10.1103/physrevb.82.165132

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