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arXiv · 1105.0150

Mott Transition in Quasi-One-Dimensional Systems

S. Moukouri·Eitan Eidelstein
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Abstract

We report the application of the density-matrix renormalization group method to a spatially anisotropic two-dimensional Hubbard model at half-filling. We find a deconfinement transition induced by the transverse hopping parameter $t_y$ from an insulator to a metal. Therefore, if $t_y$ is fixed in the metallic phase, increasing the interaction $U$ leads to a metal-to-insulator transition at a finite critical $U$. This is in contrast to the weak-coupling Hartree-Fock theory which predicts a nesting induced antiferromagnetic insulator for any $U>0$.

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S. Moukouri, Eitan Eidelstein. 2011-05-01. Mott Transition in Quasi-One-Dimensional Systems. https://doi.org/10.1103/physrevb.84.193103

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