无序外尔半金属中拓扑相变的纠缠特征
Entanglement signatures of topological phase transitions in a dirty Weyl semimetal
AI总结：
本研究探讨无序外尔半金属经历外尔节点湮灭、无序驱动金属化两种拓扑相变时，纠缠谱与纠缠熵的演化，明确无序对拓扑特征及雷尼熵标度的影响。
AI中文摘要：
三维外尔半金属（WSM）是典型的无隙拓扑相，其节点结构对包括无序在内的弱扰动具有稳定性。破坏外尔节点拓扑的两种方式是动量空间中的成对湮灭，或足够强的无序消除准粒子极点，使系统进入非费米液体扩散金属态。本研究探讨无序外尔半金属经历这两种拓扑相变时，纠缠谱与纠缠熵的演化。在无杂质极限下，WSM的拓扑由约化关联矩阵ξ=1/2本征值的轨迹体现，其镜像费米弧结构。研究表明，无序将该特征拓宽为有限宽度分布，该分布要么随节点湮灭逐渐丧失谱权重而消失，要么在金属性出现时融入背景。当调节至无序驱动的相变时，弱无序下观测到的雷尼熵标度会随系统接近临界无序强度而逐渐破缺。
英文摘要：
Three-dimensional Weyl semimetals (WSMs) constitute paradigmatic gapless topological phases whose nodal structure is stable against weak perturbations, including disorder. Two distinct ways to destroy the topology of the Weyl nodes are through pairwise annihilation in momentum space or by sufficiently strong disorder that eliminates the quasiparticle pole, driving the system into a non-Fermi-liquid diffusive-metallic state. In this work, we study the evolution of entanglement spectrum and entanglement entropy of a dirty WSM as it undergoes these two topological transitions. In the clean limit, the WSM topology is reflected by a locus of $ξ=1/2$ eigenvalues of the reduced correlation matrix mirroring the structure of Fermi arcs. We show that disorder broadens this feature into a finite-width distribution, which disappears either through a gradual loss of spectral weight upon node annihilation or by melting into the background at the onset of metallicity. When tuning across the disorder-driven transition, the scaling of the Rényi entropies observed for weak disorder gradually breaks down as the system approaches the critical disorder strength.
