Wang Chong, Gao Yuan, Lv Hongyan, Xu Xiaodong, Xiao Di
Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
Phys Rev Lett. 2020 Dec 11;125(24):247201. doi: 10.1103/PhysRevLett.125.247201.
Using bilayer CrI_{3} as an example, we demonstrate that stacking domain walls in van der Waals magnets can host one-dimensional (1D) magnon channels, which have lower energies than bulk magnons. Interestingly, some magnon channels are hidden in magnetically homogeneous background and can only be inferred with the knowledge of stacking domain walls. Compared to 1D magnons confined in magnetic domain walls, 1D magnons in stacking domain walls are more stable against external perturbations. We show that the relaxed moiré superlattices of small-angle twisted bilayer CrI_{3} is a natural realization of stacking domain walls and host interconnected moiré magnon network. Our Letter reveals the importance of stacking domain walls in understanding magnetic properties of van der Waals magnets and extends the scope of stacking engineering to magnetic dynamics.
以双层CrI₃为例，我们证明了范德华磁体中的堆叠畴壁可以容纳一维（1D）磁振子通道，其能量低于体磁振子。有趣的是，一些磁振子通道隐藏在磁均匀背景中，只有了解堆叠畴壁才能推断出来。与限制在磁畴壁中的一维磁振子相比，堆叠畴壁中的一维磁振子对外界扰动更稳定。我们表明，小角度扭曲双层CrI₃的弛豫莫尔超晶格是堆叠畴壁的自然实现，并承载相互连接的莫尔磁振子网络。我们的论文揭示了堆叠畴壁在理解范德华磁体磁性方面的重要性，并将堆叠工程的范围扩展到磁动力学。
