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Quasi-one-dimensional organic conductors: dimensional crossover and some puzzles

S. Biermann·A. Georges·T. Giamarchi·A. Lichtenstein
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Abstract

We review some properties of quasi-one-dimensional organic conductors, such as the Bechgaard salts, with an emphasis on aspects related to the crossovers between a Mott insulating state to a metallic state, and crossovers between different metallic behaviors. We discuss why a theoretical description of these issues is a particularly challenging problem, and describe a recent non-perturbative approach designed to deal with systems of coupled chains. This method, dubbed "chain-DMFT", is a generalization of dynamical mean field theory that treats both, one-dimensional and higher dimensional physics, in a unified manner. We present numerical results for a system of coupled Hubbard chains. Chain-DMFT indeed captures the metal-insulator transition and the dimensional crossover from a high temperature Luttinger liquid to a low temperature Fermi liquid phase, and allows to access the properties of these phases. Based on these results perspectives for a theoretical understanding of the physics of the Bechgaard salts are discussed.

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S. Biermann, A. Georges, T. Giamarchi, A. Lichtenstein. 2002-01-29. Quasi-one-dimensional organic conductors: dimensional crossover and some puzzles. https://arxiv.org/abs/cond-mat/0201542

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