Department of Applied Physics, Center for NanoMaterials (cNM), Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Phys Rev Lett. 2013 May 24;110(21):217204. doi: 10.1103/PhysRevLett.110.217204. Epub 2013 May 22.
We investigate a recent controversy in ultrafast magnetization dynamics by comparing the demagnetization rates from two frequently used but competing descriptions for finite temperature magnetism, namely a rigid band structure Stoner-like approach and a system of localized spins. The calculations on the localized spin system show a demagnetization rate and time comparable to experimentally obtained values, whereas the rigid band approach yields negligible demagnetization, even when the microscopic spin-flip process is assumed to be instantaneous. This shows that rigid band structure calculations will never be in quantitative agreement with experiments, irrespective of the investigated microscopic scattering mechanism.
我们通过比较两种常用于描述有限温度磁体的竞争理论（即刚性带结构的斯托纳模型和局域自旋模型）的退磁率，研究了超快磁化动力学中的一个近期争议。对局域自旋系统的计算表明，退磁率和时间与实验获得的值相当，而刚性带结构理论即使假设微观自旋翻转过程是瞬时的，也几乎没有退磁。这表明，无论所研究的微观散射机制如何，刚性带结构的计算都不会与实验定量吻合。
