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Role of Umklapp Processes in Conductivity of Doped Two-Leg Ladders

Patrick Byrne·Eugene H. Kim·Catherine Kallin
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Abstract

Recent conductivity measurements performed on the hole-doped two-leg ladder material $\mathrm{Sr_{14-x}Ca_xCu_{24}O_{41}}$ reveal an approximately linear power law regime in the c-axis DC resistivity as a function of temperature for $x=11$. In this work, we employ a bosonic model to argue that umklapp processes are responsible for this feature and for the high spectral weight in the optical conductivity which occurs beyond the finite frequency Drude-like peak. Including quenched disorder in our model allows us to reproduce experimental conductivity and resistivity curves over a wide range of energies. We also point out the differences between the effect of umklapp processes in a single chain and in the two-leg ladder.

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Patrick Byrne, Eugene H. Kim, Catherine Kallin. 2002-04-22. Role of Umklapp Processes in Conductivity of Doped Two-Leg Ladders. https://doi.org/10.1103/physrevb.66.165433

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