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arXiv · 0809.2250

Spin-Diffusion Lengths in Dilute Cu(Ge) and Ag(Sn) Alloys

Q. Fowler·B. Richard·A. Sharma·N. Theodoropoulou·R. Loloee·W. P. Pratt Jr.·J. Bass
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Abstract

We use current-perpendicular-to-plane (CPP) exchange-biased spin-valves to directly measure spin diffusion lengths lsf for N = Cu(2.1 at.%Ge) and Ag(3.6 at.%Sn) alloys. We find lsf(Cu2%Ge)) = 117+10-6 nm and lsf(Ag4%Sn)= 39 +/- 3 nm. The good agreement of this lsf(Cu2%Ge) with the value lsf(Cu2%Ge) = 121 +/- 10 nm derived from an independent spin-orbit cross-section measurement for Ge in Cu, quantitatively validates the use of Valet-Fert theory for CPP-MR data analysis to layer thicknesses several times larger than had been done before. From the value of lsf(Ag4%Sn), we predict the ESR spin-orbit cross-section for Sn impurities in Ag.

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Q. Fowler, B. Richard, A. Sharma, N. Theodoropoulou, R. Loloee, W. P. Pratt Jr., J. Bass. 2008-09-12. Spin-Diffusion Lengths in Dilute Cu(Ge) and Ag(Sn) Alloys. https://doi.org/10.1016/j.jmmm.2008.08.043

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