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Anomalous thermal conductivity of frustrated Heisenberg spin-chains and ladders

J. V. Alvarez·Claudius Gros
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Abstract

We study the thermal transport properties of several quantum spin chains and ladders. We find indications for a diverging thermal conductivity at finite temperatures for the models examined. The temperature at which the non-diverging prefactor κ^{(th)}(T) peaks is in general substantially lower than the temperature at which the corresponding specific heat c_V(T) is maximal. We show that this result of the microscopic approach leads to a substantial reduction for estimates of the magnetic mean-free path λextracted by analyzing recent experiments, as compared to similar analyses by phenomenological theories.

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J. V. Alvarez, Claudius Gros. 2002-09-09. Anomalous thermal conductivity of frustrated Heisenberg spin-chains and ladders. https://doi.org/10.1103/physrevlett.89.156603

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