title: Determining the Wiedemann-Franz ratio from the thermal hall conductivity: application to Cu and YBa2Cu3O6.95.
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 suppression. The general suppression of the WF ratio in systems with predominant electron-electron scattering is discussed.
authors.affiliation: Joseph Henry Laboratories of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: N P
authors.initials: NP
authors.lastname: Ong
authors.forename: Z A
authors.initials: ZA
authors.lastname: Xu
authors.forename: K
authors.initials: K
authors.lastname: Krishana
authors.forename: R
authors.initials: R
authors.lastname: Gagnon
authors.forename: L
authors.initials: L
authors.lastname: Taillefer