Ultrafast amplification and non-linear magneto-elastic coupling of coherent magnon modes in an antiferromagnet

Inhomogeneous magnon scattering during ultrafast demagnetization

Ni$_{0.8}$Fe$_{0.2}$ (Py) and Py alloyed with Cu exhibit intriguing ultrafast demagnetization behavior, where the Ni magnetic moment shows a delayed response relative to the Fe, an effect which is strongly enhanced by Cu alloying. We have studied a broad range of Cu concentrations to elucidate the effects of Cu alloying in Py. The orbital/spin magnetic moment ratios are largely unaffected by Cu alloying, signifying that Cu-induced changes in the ultrafast demagnetization are not related to spin-orbit interactions. We show that magnon diffusion can explain the delayed Ni response, which we attr…

Magnon-polarons in van der Waals antiferromagnet FePS3

The hybridization of magnons (spin waves) with phonons, if sufficiently strong and comprising long wavelength excitations, may offer a new playground when manipulating the magnetically ordered systems with light. Applying a magnetic field to a quasi-2D antiferromagnet, FePS3, we tune the magnon-gap excitation towards coincidence with the initially lower-in-energy phonon modes. Hybrid magnon-phonon modes, the magnon polarons are unveiled with demonstration of a pronounced avoided crossing between the otherwise bare magnon and phonon excitations. The magnon polarons in FePS3 are primary traced w…

反铁磁体中磁振子介导的热输运：与动量分辨磁振子寿命数据的联系

Magnon-mediated thermal transport in antiferromagnets: the link to momentum-resolved magnon lifetime data

固体中的输运电流通过准粒子相互碰撞以及与缺陷或边界的碰撞而衰减。由于有关碰撞寿命的信息很难获得，大多数输运性质的计算依赖于不独立已知的参数。在这里，我们使用磁振子寿命数据的二维反铁磁体Rb2MnF4计算磁振子介导的热导率没有任何可调参数，从而量化的影响，从域边界上的散射运输。相关的策略有可能大大提高我们对电子和声子准粒子热输运的理解。

Numerical Simulation of the Coupling between Split-Ring Resonators and Antiferromagnetic Magnons

We report on the results of simulations of the terahertz response of a split ring resonator (SRR) metamaterial coupled to a hypothetical antiferromagnetic material characterized by a magnon resonance. The simulations were done using finite difference time domain (FDTD) techniques. By adjusting the magnon frequency we find a hybridization of the resonant normal modes of the SRR and the magnon manifested as an avoided crossing. By varying the physical separation between the metamaterial and the antiferromagnet with a dielectric spacer, we evaluated the coupling strength between the two.

反铁磁体和交变磁体中的磁振子极化织构与输运

Magnon Polarization Textures and Transport in Antiferromagnets and Altermagnets

该研究理论分析了反铁磁体和交变磁体中磁振子的动量空间极化织构与输运，揭示了极化弛豫的两种机制，并预测了磁场方向对扩散长度和弛豫的调控效应。

基于倾斜反铁磁体 α-Fe2O3 中非互易、非简并超快自旋波的反铁磁磁振子自旋电子学

Antiferromagnetic magnon spintronic based on non-reciprocal and non-degenerated ultra-fast spin-waves in the canted antiferromagnet α-Fe2O3

本研究在 α-Fe2O3 中利用感应式与自旋电子学换能器及非局域逆自旋霍尔效应，实现了超快非互易反铁磁自旋波的传播测量与高效电学探测。

Hierarchy of magnon entanglement in antiferromagnets

Continuous variable entanglement between magnon modes in Heisenberg antiferromagnet with Dzyaloshinskii-Moryia (DM) interaction is examined. Different bosonic modes are identified, which allows to establish a hierarchy of magnon entanglement in the ground state. We argue that entanglement between magnon modes is determined by a simple lattice specific factor, together with the ratio of the strengths of the DM and Heisenberg exchange interactions, and that magnon entanglement can be detected by means of quantum homodyne techniques. As an illustration of the relevance of our findings for possibl…