Yang Xu, Li Jia-Wan, Li Yan, Qiu Liang, Xue Hao-Pu, Tang Jin, Du Hai-Feng, Sun Rui, Yang Qing-Lin, Liu Jia-Nan, Zhang Xiang-Qun, He Wei, Hou Yusheng, Cheng Zhao-Hua
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
Adv Sci (Weinh). 2025 Feb;12(6):e2411798. doi: 10.1002/advs.202411798. Epub 2024 Dec 18.
Understanding and manipulating magnetic damping, particularly in magnetic heterostructures, is crucial for fundamental research, versatile engineering, and optimization. Although magnetic damping can be enhanced by the band hybridization between ferromagnetic and nonmagnetic materials at the interface, the contribution of individual subbands on the hybridized bands to magnetic damping is fully unexplored. Here, it is found that magnetic damping α is modified by the Fermi level in Fe/GeTe heterostructures via Bi doping. By combining angle-resolved photoemission spectroscopy and density functional theory calculations, the enhancement of damping originated from the strongly hybridized band structures between Fe and the surface Rashba bands of GeTe are unveiled. More interestingly, the Fermi level modulates the density of states (DOS) ratio between the subbands of GeTe and the total DOS of hybridized states, which is directly proportional to the magnetic damping. This work gives an insightful physical understanding of the magnetic damping influenced by the hybridized band structures and opens a novel avenue to manipulate magnetic damping by band engineering.
理解并控制磁阻尼，尤其是在磁性异质结构中，对于基础研究、多功能工程和优化而言至关重要。尽管磁阻尼可通过铁磁材料与非磁性材料在界面处的能带杂化得以增强，但杂化能带中各个子带对磁阻尼的贡献仍完全未被探索。在此，研究发现通过铋掺杂，Fe/GeTe异质结构中的费米能级会改变磁阻尼α。通过结合角分辨光电子能谱和密度泛函理论计算，揭示了阻尼增强源于Fe与GeTe表面Rashba能带之间强烈杂化的能带结构。更有趣的是，费米能级调节了GeTe子带的态密度（DOS）与杂化态总DOS的比值，该比值与磁阻尼成正比。这项工作为受杂化能带结构影响的磁阻尼提供了深刻的物理理解，并开辟了一条通过能带工程控制磁阻尼的新途径。
