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arXiv · 1112.1170

Transport inefficiency in branched-out mesoscopic networks: An analog of the Braess paradox

M. G. Pala·S. Baltazar·P. Liu·H. Sellier·B. Hackens·F. Martins·V. Bayot·X. Wallart·L. Desplanque·S. Huant
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Abstract

We present evidence for a counter-intuitive behavior of semiconductor mesoscopic networks that is the analog of the Braess paradox encountered in classical networks. A numerical simulation of quantum transport in a two-branch mesoscopic network reveals that adding a third branch can paradoxically induce transport inefficiency that manifests itself in a sizable conductance drop of the network. A scanning-probe experiment using a biased tip to modulate the transmission of one branch in the network reveals the occurrence of this paradox by mapping the conductance variation as a function of the tip voltage and position.

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M. G. Pala, S. Baltazar, P. Liu, H. Sellier, B. Hackens, F. Martins, V. Bayot, X. Wallart, L. Desplanque, S. Huant. 2012-01-10. Transport inefficiency in branched-out mesoscopic networks: An analog of the Braess paradox. https://doi.org/10.1103/physrevlett.108.076802

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