Theory of Spin Loss at Metallic Interfaces

Authors

Kirill D. Belashchenko, University of Nebraska-LincolnFollow
Alexey Kovalev, University of Nebraska - LncolnFollow
Mark van Schilfgaarde, King's College LondonFollow

Date of this Version

11-11-2016

Citation

Phys. Rev. Lett. 117, 207204 (2016)
DOI: 10.1103/PhysRevLett.117.207204

Comments

© 2016 American Physical Society

Abstract

Interfacial spin-flip scattering plays an important role in magnetoelectronic devices. Spin loss at metallic interfaces is usually quantified by matching the magnetoresistance data for multilayers to the Valet-Fert model, while treating each interface as a fictitious bulk layer whose thickness is δ times the spin-diffusion length. By employing the properly generalized circuit theory and the scattering matrix approaches, we derive the relation of the parameter δ to the spin-flip transmission and reflection probabilities at an individual interface. It is found that δ is proportional to the square root of the probability of spin-flip scattering. We calculate the spin-flip scattering probabilities for flat and rough Cu/Pd interfaces using the Landauer-Büttiker method based on the first-principles electronic structure and find δ to be in reasonable agreement with experiment.