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The conductance of a multi-mode ballistic ring: beyond Landauer and Kubo

Swarnali Bandopadhyay·Yoav Etzioni·Doron Cohen
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Abstract

The Landauer conductance of a two terminal device equals to the number of open modes in the weak scattering limit. What is the corresponding result if we close the system into a ring? Is it still bounded by the number of open modes? Or is it unbounded as in the semi-classical (Drude) analysis? It turns out that the calculation of the mesoscopic conductance is similar to solving a percolation problem. The "percolation" is in energy space rather than in real space. The non-universal structures and the sparsity of the perturbation matrix cannot be ignored.

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Swarnali Bandopadhyay, Yoav Etzioni, Doron Cohen. 2008-03-03. The conductance of a multi-mode ballistic ring: beyond Landauer and Kubo. https://doi.org/10.1209/epl%2Fi2006-10360-9

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