论文标题
观察自旋 - 抗挫伤抗Fei $ _2 $中的4和6-Magnon界限
Observation of 4- and 6-magnon bound-states in the spin-anisotropic frustrated antiferromagnet FeI$_2$
论文作者
论文摘要
自旋波，例如镁是有序磁铁的常规基本激发。但是，还有其他可能性。例如，由于有吸引力的镁麦克努（Magnon-Magnon）相互作用，并且会极大地影响材料的静态和动态特性，因此可以出现镁质结合状态。在这里，我们使用时间域Terahertz光谱法展示了一个沮丧的Spin-1 Antgular Antromagnet FEI $ _2 $中不同多麦克努族准颗粒的动物园。能量磁场激发光谱包含单，二，四和六麦克尼族结合状态的特征，我们使用精确的对角线化方法对其进行分析，以用于相互作用的镁质的稀释气体。两麦克农non单子离子结合态由于各向异性强，甚至高阶激发的优势源于单离子结合状态的趋势，其本身是由于它们非常平坦的状态。这种可调的相互作用准颗粒的元素在凝聚的物质设置中提供了一个独特的平台，它让人联想到少量的量子现象，对冷原子，核和粒子物理实验中心。
Spin-waves e.g. magnons are the conventional elementary excitations of ordered magnets. However, other possibilities exist. For instance, magnon bound-states can arise due to attractive magnon-magnon interactions and drastically impact the static and dynamic properties of materials. Here, we demonstrate a zoo of distinct multi-magnon quasiparticles in the frustrated spin-1 triangular antiferromagnet FeI$_2$ using time-domain terahertz spectroscopy. The energy-magnetic field excitation spectrum contains signatures of one-, two-, four- and six-magnon bound-states, which we analyze using an exact diagonalization approach for a dilute gas of interacting magnons. The two-magnon single-ion bound states occur due to strong anisotropy and the preponderance of even higher order excitations arises from the tendency of the single-ion bound states to themselves form bound states due to their very flat dispersion. This menagerie of tunable interacting quasiparticles provides a unique platform in a condensed matter setting that is reminiscent of the few-body quantum phenomena central to cold-atom, nuclear, and particle physics experiments.
