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Small polarons and c-axis transport in highly anisotropic metals

A. F. Ho·A. J. Schofield
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Abstract

Motivated by the anomalous c-axis transport properties of the quasi two-dimensional metal, $\rm Sr_2 Ru O_4$, and related compounds, we have studied the interlayer hopping of single electrons that are coupled strongly to c-axis bosons. We find a c-axis resistivity that reflects the in-plane electronic scattering in the low and very high temperature limits (relative to the characteristic temperature of the boson $T_{\rm boson}$). For temperatures near the $T_{\rm boson}$, a broad maximum in the resistivity can appear for sufficiently strong electron-boson coupling. This feature may account for the observed ``metallic to non-metallic crossover'' seen in these layered oxides, where the boson may be a phonon.

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A. F. Ho, A. J. Schofield. 2002-11-28. Small polarons and c-axis transport in highly anisotropic metals. https://arxiv.org/abs/cond-mat/0211675

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