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Spin-dependent Transparency of Ferromagnet/Superconductor Interfaces

K. Xia·P. J. Kelly·G. E. W. Bauer·I. Turek
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Abstract

Because the physical interpretation of the spin-polarization of a ferromagnet determined by point-contact Andreev reflection (PCAR) is non-trivial, we have carried out parameter-free calculations of PCAR spectra based upon a scattering-theory formulation of Andreev reflection generalized to spin-polarized systems and a tight-binding linear muffin tin orbital method for calculating the corresponding scattering matrices. PCAR is found to measure the spin-dependent interface transparency rather than the bulk polarization of the ferromagnet which is strongly overestimated by free electron model fitting.

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K. Xia, P. J. Kelly, G. E. W. Bauer, I. Turek. 2002-02-27. Spin-dependent Transparency of Ferromagnet/Superconductor Interfaces. https://doi.org/10.1103/physrevlett.89.166603

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