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Junction of several weakly interacting quantum wires: a renormalization group study

Siddhartha Lal·Sumathi Rao·Diptiman Sen
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Abstract

We study the conductance of three or more semi-infinite wires which meet at a junction. The electrons in the wires are taken to interact weakly with each other through a short-range density-density interaction, and they encounter a general scattering matrix at the junction. We derive the renormalization group equations satisfied by the S-matrix, and we identify its fixed points and their stabilities. The conductance between any pair of wires is then studied as a function of physical parameters such as temperature. We discuss the possibility of observing the effects of junctions in present day experiments, such as the four-terminal conductance of a quantum wire and crossed quantum wires.

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Siddhartha Lal, Sumathi Rao, Diptiman Sen. 2002-06-14. Junction of several weakly interacting quantum wires: a renormalization group study. https://doi.org/10.1103/physrevb.66.165327

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