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Junctions of one-dimensional quantum wires - correlation effects in transport

X. Barnabe-Theriault·A. Sedeki·V. Meden·K. Schoenhammer
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Abstract

We investigate transport of spinless fermions through a single site dot junction of M one-dimensional quantum wires. The semi-infinite wires are described by a tight-binding model. Each wire consists of two parts: the non-interacting leads and a region of finite extent in which the fermions interact via a nearest-neighbor interaction. The functional renormalization group method is used to determine the flow of the linear conductance as a function of a low-energy cutoff for a wide range of parameters. Several fixed points are identified and their stability is analyzed. We determine the scaling exponents governing the low-energy physics close to the fixed points. Some of our results can already be derived using the non-self-consistent Hartree-Fock approximation.

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X. Barnabe-Theriault, A. Sedeki, V. Meden, K. Schoenhammer. 2005-04-04. Junctions of one-dimensional quantum wires - correlation effects in transport. https://doi.org/10.1103/physrevb.71.205327

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