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arXiv · 1107.0819

Scattering theory of magnetic/superconducting junctions with spin active interfaces

F. Romeo·R. Citro
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Abstract

We formulate a generalized scattering field theory a la Buttiker describing particles transport in magnetic/superconducting heterostructures. The proposed formalism, characterized by a four- component spinorial wavefunction of the Bogoliubov de Gennes theory, allows to describe the spin flipping phenomena induced by noncollinear magnetizations in the scattering region. As a specific application of the theory, we analyze the conductance, the magnetoresistance and the generation of spin-torque produced by an applied voltage in a spin-valve system. Quantum size effects and quantum beating patterns both in the conductance and in the spin-torque are carefully described.

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F. Romeo, R. Citro. 2011-07-05. Scattering theory of magnetic/superconducting junctions with spin active interfaces. https://doi.org/10.1103/physrevb.84.024531

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