Determining the current polarization in Al/Co nanostructured point contacts

F. Perez-Willard; J. C. Cuevas; C. Suergers; P. Pfundstein; J. Kopu; M. Eschrig; H. v. Loehneysen

doi:10.1103/physrevb.69.140502

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Determining the current polarization in Al/Co nanostructured point contacts

F. Perez-Willard·J. C. Cuevas·C. Suergers·P. Pfundstein·J. Kopu·M. Eschrig·H. v. Loehneysen

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Abstract

We present a study of the Andreev reflections in superconductor/ferromagnet nanostructured point contacts. The experimental data are analyzed in the frame of a model with two spin-dependent transmission coefficients for the majority and minority charge carriers in the ferromagnet. This model consistently describes the whole set of conductance measurements as a function of voltage, temperature, and magnetic field. The ensemble of our results shows that the degree of spin polarization of the current can be unambiguously determined using Andreev physics.

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F. Perez-Willard, J. C. Cuevas, C. Suergers, P. Pfundstein, J. Kopu, M. Eschrig, H. v. Loehneysen. 2003-06-10. Determining the current polarization in Al/Co nanostructured point contacts. https://doi.org/10.1103/physrevb.69.140502

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