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

In one-dimensional conductors with linear E-k dispersion (Dirac systems), intra-branch thermalization is favored by elastic electron-electron interaction in contrast with 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. In addition, thermoelectric power vanishes due to electron-hole symmetry, which is validated by experiment.