Field-dependent thermal conductivity and Lorenz number in Co/Cu multilayers

Kimling J, Nielsch K, Rott K, Reiss G (2013)

Publication Type: Journal article

Publication year: 2013

Journal

Physical Review B - Condensed Matter and Materials Physics American Physical Society (APS)

Book Volume: 87

Article Number: 134406

Journal Issue: 13

DOI: 10.1103/PhysRevB.87.134406

Abstract

The influence of inelastic scattering mechanisms on the giant magnetoresistance (GMR) effect has been controversially discussed. This issue can be addressed, for example, by comparing charge currents with heat currents in magnetic multilayers that exhibit GMR. The interpretation of such experiments is based on the Wiedemann-Franz law. Due to the fact that this law only holds for elastic scattering, experimentally observed deviations from this law are usually attributed to the presence of inelastic scattering and vice versa. We develop two simple models to demonstrate that this interpretation can lead to wrong conclusions in the context of the GMR effect. We employ a measurement technique that is based on the so-called 3ω method to study the in-plane electrical and thermal conductivities of a Co/Cu multilayer in dependence on magnetic fields over a wide range of temperatures. Our experimental results indicate that the Wiedemann-Franz law holds over the temperature range investigated. Using the simple models developed, we conclude that the influence of electron-magnon scattering on the GMR effect in the Co/Cu multilayer is negligible. We further conclude that electron-phonon scattering is characterized by the same spin asymmetry as the predominant elastic scattering of electrons at interfaces in the Co/Cu multilayer. © 2013 American Physical Society.

Involved external institutions

Universität Hamburg (UHH) DE Germany (DE) Universität Bielefeld DE Germany (DE)

How to cite

APA:

Kimling, J., Nielsch, K., Rott, K., & Reiss, G. (2013). Field-dependent thermal conductivity and Lorenz number in Co/Cu multilayers. Physical Review B - Condensed Matter and Materials Physics, 87(13). https://dx.doi.org/10.1103/PhysRevB.87.134406

MLA:

Kimling, Johannes, et al. "Field-dependent thermal conductivity and Lorenz number in Co/Cu multilayers." Physical Review B - Condensed Matter and Materials Physics 87.13 (2013).

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