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Mn L3,2 X-ray Absorption Spectroscopy And Magnetic Circular Dichroism In Ferromagnetic (Ga,Mn)P

P. R. Stone·M. A. Scarpulla·R. Farshchi·I. D. Sharp·J. W. Beeman·K. M. Yu·E. Arenholz·J. D. Denlinger·E. E. Haller·O. D. Dubon
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Abstract

We have measured the X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) at the Mn L3,2 edges in ferromagnetic Ga1-xMnxP films for 0.018<x<0.042. Large XMCD asymmetries at the L3 edge indicate significant spin-polarization of the density of states at the Fermi energy. The spectral shapes of the XAS and XMCD are nearly identical with those for Ga1-xMnxAs indicating that the hybridization of Mn d states and anion p states is similar in the two materials. Finally, compensation with sulfur donors not only lowers the ferromagnetic Curie temperature but also reduces the spin polarization of the hole states.

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P. R. Stone, M. A. Scarpulla, R. Farshchi, I. D. Sharp, J. W. Beeman, K. M. Yu, E. Arenholz, J. D. Denlinger, E. E. Haller, O. D. Dubon. 2006-07-15. Mn L3,2 X-ray Absorption Spectroscopy And Magnetic Circular Dichroism In Ferromagnetic (Ga,Mn)P. https://doi.org/10.1063/1.2730317

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