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Induced Ge Spin Polarization at the Fe/Ge Interface

J. W. Freeland·R. H. Kodama·M. Vedpathak·S. C. Erwin·D. J. Keavney·R. Winarski·P. Ryan·R. A. Rosenberg
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Abstract

We report direct experimental evidence showing induced magnetic moments on Ge at the interface in an Fe/Ge system. Details of the x-ray magnetic circular dichroism and resonant magnetic scattering at the Ge L edge demonstrate the presence of spin-polarized {\it s} states at the Fermi level, as well as {\it d} character moments at higher energy, which are both oriented antiparallel to the moment of the Fe layer. Use of the sum rules enables extraction of the L/S ratio, which is zero for the {\it s} part and $\sim0.5$ for the {\it d} component. These results are consistent with layer-resolved electronic structure calculations, which estimate the {\it s} and {\it d} components of the Ge moment are anti-parallel to the Fe {\it 3d} moment and have a magnitude of $\sim0.01 μ_B$.

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J. W. Freeland, R. H. Kodama, M. Vedpathak, S. C. Erwin, D. J. Keavney, R. Winarski, P. Ryan, R. A. Rosenberg. 2003-07-25. Induced Ge Spin Polarization at the Fe/Ge Interface. https://doi.org/10.1103/physrevb.70.033201

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