Terahertz permeability of hard ferromagnetic L10-FePt alloy nanowire
Terahertz permeability of hard ferromagnetic L10-FePt alloy nanowire
复制标题
硬铁磁L10-FePt合金纳米线的太赫兹磁导率
DOI：
10.1088/1361-6528/aca7cd
复制
发表时间：
2022
期刊：
影响因子：
3.5
通讯作者：
M. Han
中科院分区：
文献类型：
--
作者：
M. Han
一般认为铁磁材料的动态磁响应很弱，无法在太赫兹领域得到应用。然而，我们在这篇论文中的结果表明，太赫兹（THz）磁导率的隔离L10-FePt合金纳米线具有超硬铁磁性能是显着的0.348 THz，只要它是在适当的reflectance状态（例如，Mr/Ms = 1.0），这是以往认为只有在某些超材料。与单一Fe纳米线的GHz磁导率相比，L10-FePt的THz磁导率谱显示出明显的不同。发现反常的负磁导率虚部（μ″ < 0）与等效负阻尼常数有关，并从FePt纳米线THz自然共振反常进动的角度解释了这一现象.
It is commonly thought that ferromagnetic materials can not find applications in terahertz domain because of their very weak dynamic magnetic responses. However, our results in this paper show that the terahertz (THz) permeability of an isolated L10-FePt alloy nanowire with super hard ferromagnetic properties is significant at 0.348 THz, as long as it is at proper remanent states (for instance, Mr/Ms = 1.0), which are ever thought only possible in some metamaterials. Compared to the gigahertz (GHz) permeability of single Fe nanowire, the THz permeability spectra of L10-FePt are shown obviously different. Unusual negative imaginary parts of permeability (μ″ < 0) is found related to the equivalent negative damping constant, which is explained from the perspective of abnormal precession of natural resonance at THz for FePt nanowire.