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Impurity and correlation effects on transport in one-dimensional quantum wires

T. Enss·V. Meden·S. Andergassen·X. Barnabe-Theriault·W. Metzner·K. Schoenhammer
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Abstract

We study transport through a one-dimensional quantum wire of correlated fermions connected to semi-infinite leads. The wire contains either a single impurity or two barriers, the latter allowing for resonant tunneling. In the leads the fermions are assumed to be non-interacting. The wire is described by a microscopic lattice model. Using the functional renormalization group we calculate the linear conductance for wires of mesoscopic length and for all relevant temperature scales. For a single impurity, either strong or weak, we find power-law behavior as a function of temperature. In addition, we can describe the complete crossover from the weak- to the strong-impurity limit. For two barriers, depending on the parameters of the enclosed quantum dot, we find temperature regimes in which the conductance follows power-laws with "universal" exponents as well as non-universal behavior. Our approach leads to a comprehensive picture of resonant tunneling. We compare our results with those of alternative approaches.

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T. Enss, V. Meden, S. Andergassen, X. Barnabe-Theriault, W. Metzner, K. Schoenhammer. 2005-01-17. Impurity and correlation effects on transport in one-dimensional quantum wires. https://doi.org/10.1103/physrevb.71.155401

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