Title: Myriad of Terahertz Magnons with All-Optical Magnetoelectric Functionality for Efficient Spin-Wave Computing in Honeycomb Magnet Co4Ta2O9 Show Chinese title

Title: 蜂窝磁体Co4Ta2O9中用于高效自旋波计算的众多太赫兹磁振子，具有全光磁电功能

Abstract: Terahertz (THz) magnonics represent the notion of mathematical algebraic operations of magnons such as addition and subtraction in THz regime which is an emergent dissipationless ultrafast alternative to existing data processing technologies. Spin waves on antiferromagnets with a twist in spin order host such magnons in THz regime, which possess advantage of higher processing speeds, additional polarization degree of freedom and longer propagation lengths compared to that of gigahertz magnons in ferromagnets. While interaction among THz magnons is the crux of algebra operations, it requires magnetic orders with closely spaced magnon modes for easier experimental realization of their interactions. Herein, rich wealth of magnons spanning a narrow energy range of 0.4 to 10 meV is unraveled in Co4Ta2O9 using magneto-THz spectroscopy. Rare multitude of ten excitation modes, either of magnons or hybrid magnon-phonon modes is presented. Among other attributes, spin lattice interaction suggests a correlation among spin and local lattice distortion, magnetostriction, and magnetic exchange interaction signifying a THz magnetoelectric effect. This unification of structural, magnetic and dielectric facets, and their magnetic field control in a narrow spectrum unwinds the mechanism underneath the system's complexity while the manifestation of multitude of spin excitation modes is a potential source to design multiple channels in spin-wave computing based devices. Show Chinese abstract

Abstract: 太赫兹（THz）磁子学代表了在太赫兹范围内对磁子进行数学代号运算的概念，如加法和减法，这是现有数据处理技术的一种无耗散的超快替代方案。 具有自旋顺序扭曲的反铁磁体上的自旋波在太赫兹范围内承载这样的磁子，与铁磁体中的千兆赫兹磁子相比，它们具有更高的处理速度、额外的极化自由度和更长的传播长度的优势。 虽然太赫兹磁子之间的相互作用是代数运算的核心，但需要磁序中紧密间隔的磁子模式，以便更容易地实现其相互作用的实验。 在此，使用磁-太赫兹光谱学在Co4Ta2O9中揭示了跨越0.4至10 meV窄能量范围的丰富磁子财富。 展示了十种激发模式，无论是磁子还是混合磁子-声子模式。 除了其他属性外，自旋晶格相互作用表明自旋和局部晶格畸变、磁致伸缩以及磁交换相互作用之间存在相关性，表明存在太赫兹磁电效应。 这种结构、磁性和介电特性的统一及其在窄谱中的磁场控制解开了系统复杂性的机制，而多种自旋激发模式的出现是设计基于自旋波计算设备的多通道的潜在来源。