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arXiv · 2208.09144

The Wiedemann-Franz law in doped Mott insulators without quasiparticles

Wen O. Wang·Jixun K. Ding·Yoni Schattner·Edwin W. Huang·Brian Moritz·Thomas P. Devereaux
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Abstract

Many metallic quantum materials display anomalous transport phenomena that defy a Fermi liquid description. Here, we use numerical methods to calculate thermal and charge transport in the doped Hubbard model and observe a cross-over separating high- and low-temperature behaviors. Distinct from the behavior at high temperatures, the Lorenz number $L$ becomes weakly doping dependent and less sensitive to parameters at low temperatures. At the lowest numerically accessible temperatures, $L$ roughly approaches the Wiedemann-Franz constant $L_0$, even in a doped Mott insulator that lacks well-defined quasiparticles. Decomposing the energy current operator indicates a compensation between kinetic and potential contributions, which may help to clarify the interpretation of transport experiments beyond Boltzmann theory in strongly correlated metals.

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Wen O. Wang, Jixun K. Ding, Yoni Schattner, Edwin W. Huang, Brian Moritz, Thomas P. Devereaux. 2022-08-19. The Wiedemann-Franz law in doped Mott insulators without quasiparticles. https://doi.org/10.1126/science.ade3232

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