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arXiv · 0807.4756

Restricted Wiedemann-Franz law and vanishing thermoelectric power in one-dimensional conductors

Marcelo Kuroda·Jean-Pierre Leburton
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Abstract

In one-dimensional (1D) conductors with linear E-k dispersion (Dirac systems) intrabranch thermalization is favored by elastic electron-electron interaction in contrast to electron systems with a nonlinear (parabolic) dispersion. We show that under external electric fields or thermal gradients the carrier populations of different branches, treated as Fermi gases, have different temperatures as a consequence of self-consistent carrier-heat transport. Specifically, in the presence of elastic phonon scattering, the Wiedemann-Franz law is restricted to each branch with its specific temperature and is characterized by twice the Lorenz number. In addition thermoelectric power vanishes due to electron-hole symmetry, which is validated by experiment.

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Marcelo Kuroda, Jean-Pierre Leburton. 2008-07-29. Restricted Wiedemann-Franz law and vanishing thermoelectric power in one-dimensional conductors. https://doi.org/10.1103/physrevlett.101.256805

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