论文标题
边界附近纠缠中o（1）的奇偶校验效应和普遍的术语
Parity effects and universal terms of O(1) in the entanglement near a boundary
论文作者
论文摘要
在存在边界的情况下，已知晶格模型中的纠缠熵表现出振荡的振荡，该子系统的长度（均等）长度随着距离距离的增加而衰减为零。我们在本文中指出，当子系统从边界开始并以杂质结束时，出现纠缠（以及电荷波动）的振荡不会随着距离而衰减，并且表现出通用的特征。我们对XX链的情况进行了详细研究，其中一个修改后的链接（一个保形缺陷）或两个连续的修改链接（相关的缺陷），无论是在数值和分析上都是相关的缺陷）。然后，我们将分析概括为扩展（保形）杂质的情况，我们将其解释为与金属铅相连的SSH模型。在这种情况下，可以根据非平凡拓扑阶段的存在来解释平价效应。
In the presence of boundaries, the entanglement entropy in lattice models is known to exhibit oscillations with the (parity of the) length of the subsystem, which however decay to zero with increasing distance from the edge. We point out in this article that, when the subsystem starts at the boundary and ends at an impurity, oscillations of the entanglement (as well as of charge fluctuations) appear which do not decay with distance, and which exhibit universal features. We study these oscillations in detail for the case of the XX chain with one modified link (a conformal defect) or two successive modified links (a relevant defect), both numerically and analytically. We then generalize our analysis to the case of extended (conformal) impurities, which we interpret as SSH models coupled to metallic leads. In this context, the parity effects can be interpreted in terms of the existence of non-trivial topological phases.
