论文标题
Kagome-lattice Metallic Antallic Anterlomagnet Fe $ _ {0.89} $ co $ _ {0.11} $ sn中的旋转激发
Spin excitations in the kagome-lattice metallic antiferromagnet Fe$_{0.89}$Co$_{0.11}$Sn
论文作者
论文摘要
由于寻求超导性，量子自旋液态和拓扑电子结构的广泛前景，kagome-lattice材料引起了极大的兴趣。其中，过渡金属的晶格是拓扑特性，丰富的磁性和多轨物理学组合的备受瞩目的对象。在这里，我们报告了一项关于Kagome-lattice抗磁性金属Fe $ _ {0.89} $ co $ _ {0.11} $ sn的旋转动力学的非弹性中子散射研究。尽管可以观察到磁性激励最多可达$ \ sim $ 250 MEV，但仅在$ \ sim $ 90 MEV以下确定了明确定义的自旋波，并且可以使用Heisenberg交换与Ferromagnetic In-Plane in-Plane neighbor近距离交易所进行建模在线性自旋波理论下耦合$ j_c $。自旋波在$ \ sim $ 90 MEV上方，进入流动的石膏连续体，并成为高度阻尼的粒子孔激发。在布里渊区的K点，我们揭示了旋转波的可能带交叉，这表明潜在的狄拉克木蛋白。我们的结果揭示了旋转激发从平面AFM状态到轴向AFM状态的演变，以Fe $ _ {0.89} $ co $ _ {0.11} $ sn，解决两个状态的磁性哈密顿量，并确认务必的磁性对旋转兴奋的重要影响。
Kagome-lattice materials have attracted tremendous interest due to the broad prospect for seeking superconductivity, quantum spin liquid states, and topological electronic structures. Among them, the transition-metal kagome lattices are high-profile objects for the combination of topological properties, rich magnetism, and multiple-orbital physics. Here we report an inelastic neutron scattering study on the spin dynamics of a kagome-lattice antiferromagnetic metal Fe$_{0.89}$Co$_{0.11}$Sn. Although the magnetic excitations can be observed up to $\sim$250 meV, well-defined spin waves are only identified below $\sim$90 meV and can be modeled using Heisenberg exchange with ferromagnetic in-plane nearest-neighbor coupling $J_1$, in-plane next-nearest-neighbor coupling $J_2$, and antiferromagnetic (AFM) interlayer coupling $J_c$ under linear spin-wave theory. Above $\sim$90 meV, the spin waves enter the itinerant Stoner continuum and become highly damped particle-hole excitations. At the K point of the Brillouin zone, we reveal a possible band crossing of the spin wave, which indicates a potential Dirac magnon. Our results uncover the evolution of the spin excitations from the planar AFM state to the axial AFM state in Fe$_{0.89}$Co$_{0.11}$Sn, solve the magnetic Hamiltonian for both states, and confirm the significant influence of the itinerant magnetism on the spin excitations.
