发表机构
University of Warsaw（华沙大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文通过线性自旋波理论证明，局域自旋激发的实空间传播模式可作为区分交错磁性与传统磁序的动力学指纹，并揭示J_2符号变化对传播模式的影响。
AI 中文摘要
区分交错磁性与传统铁磁性和反铁磁性通常依赖于动量空间探针。在此，我们证明局域自旋激发的实空间扩展提供了交错磁序的独特动力学指纹。利用具有最近邻和次近邻耦合J_1和J_2的二维棋盘格上的线性自旋波理论，我们证明有限的J_2产生方向相关的磁振子群速度，并将两个磁振子分支分裂。由此产生的传播仍比铁磁体更接近反铁磁体，保持近似圆形的外波前，而方向相关的磁振子速度在该波前内部产生显著的十字形空间结构。我们进一步表明，改变J_2的符号进入无阻挫区域（J_2<0）会增加特征传播速度，并交换增强传播的对角方向，对应于各向异性空间模式的π/2旋转。这些结果确立了时空动力学作为交错磁振子的互补探针，为通过固态和合成量子系统中的实空间传播模式识别非常规磁序提供了途径。
英文摘要
Distinguishing altermagnetism from conventional ferromagnetism and antiferromagnetism typically relies on momentum-space probes. Here, we show that the real-space spreading of a localized spin excitation provides a distinctive dynamical fingerprint of altermagnetic order. Using linear spin-wave theory on a two-dimensional checkerboard lattice with nearest-neighbor and next-nearest-neighbor couplings J_1 and J_2, we demonstrate that finite J_2 produces direction-dependent magnon group velocities and splits the two magnon branches. The resulting propagation remains closer to that of an antiferromagnet than a ferromagnet, retaining an approximately circular outer wavefront, while the direction-dependent magnon velocities produce a pronounced cross-like spatial structure inside this front. We further show that changing the sign of J_2 to enter the unfrustrated regime (J_2<0) increases the characteristic propagation velocities and interchanges the diagonal directions of enhanced propagation, corresponding to a pi/2 rotation of the anisotropic spatial pattern. These results establish spacetime dynamics as a complementary probe of altermagnetic magnons, providing a route to identifying unconventional magnetic order through real-space propagation patterns in solid-state and synthetic quantum systems.
Comments10 pages, 7 figures
