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Failure of the Wiedemann-Franz Law in Mesoscopic Conductors

Maxim G. Vavilov·A. Douglas Stone
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Abstract

We study the effect of mesoscopic fluctuations on the validity of the Wiedemann--Franz (WF) law for quasi-one-dimensional metal wires and open quantum dots. At temperatures much less than the generalized Thouless energy, E_c, the WF law is satisfied for each specific sample but as the temperature is raised through E_c a sample-specific correction to the WF law of order 1/g appears (g is the dimensionless conductance) and then tends to zero again at high temperatures. The mesoscopic violation of the Weidemann-Franz law is even more pronounced in a ring geometry, for which Lorenz number exhibits h/e flux-periodic Aharonov-Bohm oscillations.

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Maxim G. Vavilov, A. Douglas Stone. 2005-12-20. Failure of the Wiedemann-Franz Law in Mesoscopic Conductors. https://doi.org/10.1103/physrevb.72.205107

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