Elliott-Yafet mechanism and the discussion of femtosecond magnetization dynamics
Elliott-Yafet mechanism and the discussion of femtosecond magnetization dynamics
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DOI：
10.1103/physrevb.79.140401
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发表时间：
2009-04-01
影响因子：
3.7
通讯作者：
Faehnle, M.
中科院分区：
文献类型：
--
作者：
Steiauf, D.;Faehnle, M.
在过去，人们一直质疑是否埃利奥特-Yafet机制的自旋翻转散射的电子在声子可以解释超快退磁的铁磁体（主要是镍）飞秒激光激发后。其原因是Ni的Elliott-Yafet自旋混合参数B（2）的值还不知道，并且被认为是非常小的Cu（其是周期表中的最近邻）的值。本文用密度泛函电子理论计算了Co、Fe、Ni、Cu、Au和K的B（2）。对于Co、Fe和Ni，B（2）比通常假定的Cu的值大25倍左右。这一结果应支持Elliott-Yafet机制在fs磁化动力学的讨论。
In the past it has been questioned whether the Elliott-Yafet mechanism of spin-flip scattering of electrons at phonons may explain the ultrafast demagnetization of a ferromagnet (mostly Ni) after femtosecond laser excitation. The reason has been that the value of the Elliott-Yafet spin-mixing parameter b(2) of Ni has not been known and has been taken as the one of Cu (which is the nearest neighbor in the periodic table) which is very small. We present calculations of b(2) by the ab initio density-functional electron theory for Co, Fe, Ni, Cu, Au, and K. For Co, Fe, and Ni b(2) is about a factor of 25 larger than the value commonly assumed for Cu. This result should support the Elliott-Yafet mechanism in the discussion of fs magnetization dynamics.