论文标题
超金属磁化动力学的超金属化动力学$ _2 $ feal heusler合金
Ultrafast magnetization dynamics in half-metallic Co$_2$FeAl Heusler alloy
论文作者
论文摘要
我们报告了由时间分辨的磁光 - 光学kerr效应探测的Heusler Alloy $ \ mathrm {Co_ {2} feal} $中的光学诱导的超快磁化动力学。将实验结果与电子结构理论和原子自旋动力学模拟的结果进行比较。在实验上，我们发现在$ \ mathrm {co_ {2} feal} $的胶片中的电磁时间（$τ_{m} $）几乎与变化的结构顺序无关，并且与元素3D Ferromagnets中的结构相似。相比之下，发现在$τ_{r} $指定的磁化恢复过程较慢，是在picsecond Time量表上发生的，并且被证明与Gilbert Damping参数（$α$）密切相关。我们的结果表明，$ \ mathrm {co_ {2} feal} $是唯一的，因为它是第一种清楚地证明在remagnetization过程中减震参数重要性的材料。基于这些结果，我们认为对于$ \ mathrm {co_ {2} feal} $，remagnetization过程以镁动力学为主导，这可能具有一般适用性。
We report on optically induced, ultrafast magnetization dynamics in the Heusler alloy $\mathrm{Co_{2}FeAl}$, probed by time-resolved magneto-optical Kerr effect. Experimental results are compared to results from electronic structure theory and atomistic spin-dynamics simulations. Experimentally, we find that the demagnetization time ($τ_{M}$) in films of $\mathrm{Co_{2}FeAl}$ is almost independent of varying structural order, and that it is similar to that in elemental 3d ferromagnets. In contrast, the slower process of magnetization recovery, specified by $τ_{R}$, is found to occur on picosecond time scales, and is demonstrated to correlate strongly with the Gilbert damping parameter ($α$). Our results show that $\mathrm{Co_{2}FeAl}$ is unique, in that it is the first material that clearly demonstrates the importance of the damping parameter in the remagnetization process. Based on these results we argue that for $\mathrm{Co_{2}FeAl}$ the remagnetization process is dominated by magnon dynamics, something which might have general applicability.
