Scheck C, Cheng L, Barsukov I, Frait Z, Bailey W E
Materials Science, Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA.
Phys Rev Lett. 2007 Mar 16;98(11):117601. doi: 10.1103/PhysRevLett.98.117601. Epub 2007 Mar 12.
The longest relaxation time and sharpest frequency content in ferromagnetic precession is determined by the intrinsic (Gilbert) relaxation rate G. For many years, pure iron (Fe) has had the lowest known value of G = 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 +/- 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.
铁磁进动中最长的弛豫时间和最尖锐的频率成分由本征（吉尔伯特）弛豫率G决定。多年来，对于所有纯铁磁金属或二元合金而言，纯铁（Fe）的G值最低，为57兆赫。我们表明，含钒（V）的外延铁合金在含27% V时G值显著降低至35±5兆赫。该结果可理解为自旋轨道耦合在产生弛豫中的作用，通过原子序数Z降低。
