Abstract
We study the ratio of the energy and particle currents () in an integrable one-dimensional system of interacting fermions. Both currents are driven by a finite (nonzero) dc electric field. In doped insulators, where the local conserved quantities saturate the so-called Mazur bound on the charge stiffness, agrees with the linear-response theory, even though such agreement may be violated for each current alone. However, in the metallic regime with a nonsaturated Mazur bound, the ratio in a driven system is shown to be much larger than predicted by the linear-response theory.
- Received 11 September 2014
- Revised 24 October 2014
DOI:https://doi.org/10.1103/PhysRevB.90.195119
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