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The Wiedemann-Franz law in the SU(N) Wolff model

Balázs Dóra
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Abstract

We study the electrical and thermal transport through the SU(N) Wolff model with the use of bosonization. The Wilson ratio reaches unity as N grows to infinity. The electric conductance is dominated by the charge channel, and decreases monotonically with increasing interaction. The thermal conductivity enhances in the presence of local Hubbard U. The Wiedemann-Franz law is violated, the Lorentz number depends strongly on the interaction parameter, which can be regarded as a manifestation of spin-charge separation.

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Balázs Dóra. 2006-02-16. The Wiedemann-Franz law in the SU(N) Wolff model. https://doi.org/10.1103/physrevb.74.161101

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