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Violation of the Wiedemann-Franz Law in a Large-N Solution of the t-J Model

A. Houghton·S. Lee·J. B. Marston
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Abstract

We show that the Wiedemann-Franz law, which holds for Landau Fermi liquids, breaks down in a large-n treatment of the t-J model. The calculated ratio of the in-plane thermal and electrical conductivities agrees quantitatively with experiments on the normal state of the electron-doped Pr_{2-x}Ce_xCuO_4 (x = 0.15) cuprate superconductor. The violation of the Wiedemann-Franz law in the uniform phase contrasts with other properties of the phase that are Fermi liquid like.

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A. Houghton, S. Lee, J. B. Marston. 2002-03-08. Violation of the Wiedemann-Franz Law in a Large-N Solution of the t-J Model. https://doi.org/10.1103/physrevb.65.220503

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