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arXiv · 2208.10670

Following enhanced Sm spin projection in Gd$_x$Sm$_{1-x}$N

J. D. Miller·J. F. McNulty·B. J. Ruck·M. Al Khalfioui·S. Vézian·M. Suzuki·H. Osawa·N. Kawamura·H. J. Trodahl
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Abstract

The rare-earth nitrides form a series of structurally simple $intrinsic$ ferromagnetic semiconductors, a rare class of both fundamental interest and application potential. Within the series there is a wide range of magnetic properties relating to the spin/orbit contributions to the ferromagnetic ground states. We report an x-ray magnetic circular dichroism investigation of the spin/orbit magnetic dipole alignments of Sm and Gd ions in epitaxial Gd$_x$Sm$_{1-x}$N films. The Sm spin-alignment expectation value $\langle S_{z} \rangle$ is seen to be strengthened by the Gd/Sm exchange interaction, providing guidance concerning the composition for an angular momentum compensation point (where the volume-averaged total angular momentum of a film is zero).

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J. D. Miller, J. F. McNulty, B. J. Ruck, M. Al Khalfioui, S. Vézian, M. Suzuki, H. Osawa, N. Kawamura, H. J. Trodahl. 2022-08-23. Following enhanced Sm spin projection in Gd$_x$Sm$_{1-x}$N. https://doi.org/10.1103/physrevb.106.174432

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