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One-Dimensional Multi-Band Correlated Conductors and Anderson Impurity Physics

Michele Fabrizio·Erio Tosatti
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Abstract

A single Anderson impurity model recently predicted, through its unstable fixed point, the phase diagram of a two band model correlated conductor, well confirmed by Dynamical Mean Field Theory in infinite dimensions. We study here the one dimensional version of the same model and extract its phase diagram in this opposite limit of reduced dimensionality. As expected for one dimension, the Mott metal-insulator transition at half filling is replaced by a dimerized insulator-undimerized Mott insulator transition, while away from half filling the strongly correlated superconductivity for inverted Hund's rule exchange in infinite dimensions is replaced by dominant pairing fluctuations. Many other aspects of the one dimensional system, in particular the field theories and their symmetries are remarkably the same as those of the Anderson impurity, whose importance appears enhanced.

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Michele Fabrizio, Erio Tosatti. 2004-10-28. One-Dimensional Multi-Band Correlated Conductors and Anderson Impurity Physics. https://doi.org/10.1103/physrevlett.94.106403

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