发表机构
University of Oslo; Helmholtz-Zentrum Berlin für Materialien und Energie; Freie Universität Berlin; The University of Tokyo（奥斯陆大学; 柏林亥姆霍兹材料能源研究中心; 柏林自由大学; 东京大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究对自旋各向同性螺旋自旋液体中的拓扑缺陷进行分类，发现分数半涡旋及其融合规则，并通过模拟揭示其在低温下的行为。
AI 中文摘要
螺旋自旋液体是一类磁性状态，其经典基态流形由平面非公度自旋螺旋构成，这些螺旋的波矢位于倒空间中连续的环或表面上。由此产生的亚广延简并抑制了磁长程有序，并导致类似液体的行为。尽管已有众多材料实现和理论研究，自旋各向同性海森堡螺旋自旋液体的低温自旋构型结构仍未被充分理解。在此，我们对这些系统所支持的经典拓扑缺陷进行了分类和表征。我们揭示了一个丰富的涡旋类型族，涉及自旋方向、螺旋平面法线和波矢取向的协同缠绕，从而得到$\mathbb{Z} \times \mathbb{Z}_2$分类。值得注意的是，基本缺陷是半涡旋，在自旋和动量空间中携带分数化的$2\pi$缠绕，并遵循类似于伊辛任意子的融合规则。对方格螺旋自旋液体的大规模经典模拟表明，这些涡旋在螺旋自旋液体区域中密集存在，并在序由无序相变之下紧密束缚，最终融合至真空。
英文摘要
Spiral spin liquids are magnetic states whose classical ground-state manifold consists of planar incommensurate spin spirals with wave vectors lying on a continuous ring or surface in reciprocal space. The resulting subextensive degeneracy suppresses magnetic long-range order and gives rise to liquid-like behavior. Despite numerous material realizations and theoretical investigations, the structure of low-temperature spin configurations of spin-isotropic Heisenberg spiral spin liquids has remained poorly understood. Here, we classify and characterize the classical topological defects supported by these systems. We uncover a rich family of vortex types involving concerted windings of spin directions, spiral-plane normals, and wave-vector orientations, yielding a $\mathbb{Z} \times \mathbb{Z}_2$ classification. Remarkably, the elementary defects are half-vortices carrying fractional $2π$ windings in both spin and momentum space and obey fusion rules resembling to those of Ising anyons. Large-scale classical simulations of a square-lattice spiral spin liquid reveal that these vortices are dense in the spiral-spin-liquid regime, and bind tightly below an order-by-disorder phase transition, eventually fusing to vacuum.
