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arXiv · 1211.5809

Equivalence of single-particle and transport lifetimes from hybridization fluctuations

I. Paul·C. Pépin·M. R. Norman
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Abstract

Single band theories of quantum criticality successfully describe a single-particle lifetime with non-Fermi liquid temperature dependence. But, they fail to obtain a charge transport rate with the same dependence unless the interaction is assumed to be momentum independent. Here we demonstrate that a quantum critical material, with a long range mode that transmutes electrons between light and heavy bands, exhibits a quasi-linear temperature dependence for {\it both} the single-particle and the charge transport lifetimes, despite the strong momentum dependence of the interaction.

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I. Paul, C. Pépin, M. R. Norman. 2012-11-25. Equivalence of single-particle and transport lifetimes from hybridization fluctuations. https://doi.org/10.1103/physrevlett.110.066402

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