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Determining the Wiedemann-Franz ratio from the thermal Hall conductivity: Application to Cu and YBa_2Cu_3O_6.95

Y. Zhang·N. P. Ong·Z. A. Xu·R. Gagnon·L. Taillefer
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Abstract

The Wiedemann-Franz (WF) ratio compares the thermal and electrical conductivities in a metal. We describe a new way to determine its value, based on the thermal Hall conductivity. The technique is applied to copper and to untwinned YBaCuO. In the latter, we uncover a T-linear dependence and suppression of the Hall-channel WF ratio. We discuss the implications of this suppressions. The general suppression of the WF ratio in systems with predominant electron-electron scattering is discussed.

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Y. Zhang, N. P. Ong, Z. A. Xu, R. Gagnon, L. Taillefer. 2000-01-04. Determining the Wiedemann-Franz ratio from the thermal Hall conductivity: Application to Cu and YBa_2Cu_3O_6.95. https://doi.org/10.1103/physrevlett.84.2219

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