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Scaling of the conductance in a quantum wire

V. Meden·S. Andergassen·W. Metzner·U. Schollwoeck·K. Schoenhammer
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Abstract

The conductance G of an interacting nano-wire containing an impurity and coupled to non-interacting semi-infinite leads is studied using a functional renormalization group method. We obtain results for microscopic lattice models without any further idealizations. For an interaction which is turned on smoothly at the contacts we show that one-parameter scaling of G holds. If abrupt contacts are included we find power-law suppression of G with an exponent which is twice as large as the one obtained for smooth contacts and no one-parameter scaling. Our results show excellent agreement with the analytically known scaling function at Luttinger liquid parameter K=1/2 and numerical density-matrix renormalization group data.

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V. Meden, S. Andergassen, W. Metzner, U. Schollwoeck, K. Schoenhammer. 2003-07-18. Scaling of the conductance in a quantum wire. https://doi.org/10.1209/epl%2Fi2003-00624-x

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