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arXiv · 0708.0545

Critical conductance of a one-dimensional doped Mott insulator

Abstract

We consider the two-terminal conductance of a one-dimensional Mott insulator undergoing the commensurate-incommensurate quantum phase transition to a conducting state. We treat the leads as Luttinger liquids. At a specific value of compressibility of the leads, corresponding to the Luther-Emery point, the conductance can be described in terms of the free propagation of non-interacting fermions with charge e/\sqrt{2}. At that point, the temperature dependence of the conductance across the quantum phase transition is described by a Fermi function. The deviation from the Luther-Emery point in the leads changes the temperature dependence qualitatively. In the metallic state, the low-temperature conductance is determined by the properties of the leads, and is described by the conventional Luttinger liquid theory. In the insulating state, conductance occurs via activation of e/\sqrt{2} charges, and is independent of the Luttinger liquid compressibility.

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M. Garst, D. S. Novikov, Ady Stern, L. I. Glazman. 2008-01-23. Critical conductance of a one-dimensional doped Mott insulator. https://doi.org/10.1103/physrevb.77.035128

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