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Low relaxation rate in a low-Z alloy of iron

C. Scheck·L. Cheng·I. Barsukov·Z. Frait·W. E. Bailey
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Abstract

The longest relaxation time and sharpest frequency content in ferromagnetic precession is determined by the intrinsic (Gilbert) relaxation rate \emph{$G$}. For many years, pure iron (Fe) has had the lowest known value of $G=\textrm{57 Mhz}$ for all pure ferromagnetic metals or binary alloys. We show that an epitaxial iron alloy with vanadium (V) possesses values of $G$ which are significantly reduced, to 35$\pm$5 Mhz at 27% V. The result can be understood as the role of spin-orbit coupling in generating relaxation, reduced through the atomic number $Z$.

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C. Scheck, L. Cheng, I. Barsukov, Z. Frait, W. E. Bailey. 2006-12-30. Low relaxation rate in a low-Z alloy of iron. https://doi.org/10.1103/physrevlett.98.117601

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