Violation of the magnonic Wiedemann-Franz law in the strong nonlinear regime

  title={Violation of the magnonic Wiedemann-Franz law in the strong nonlinear regime},
  author={Kouki Nakata and Yuichi Ohnuma and Se Kwon Kim},
  journal={Physical Review B},
The celebrated Wiedemann-Franz (WF) law which governs the relation between charge and heat transport traces back to the experimental discovery in 1853 by Wiedemann and Franz. Despite the fundamental difference of the quantum-statistical properties between fermions and bosons, the linear-in- T behavior of the WF law at low temperatures has recently been found to be the universal property by the discovery of the WF law for magnon transport. However, the WF law is for the linear response, and… 


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