论文标题
二维晶格理论中无序的定位过渡
Disorder-free localization transition in a two-dimensional lattice gauge theory
论文作者
论文摘要
无障碍定位是一种新颖的终生性破坏机制，可以在相互作用的量子多体系统（例如晶格计理论（LGT））中发生。尽管对于常规的多体定位，量子定位过渡（QLT）的性质仍在争论中，但在这里，我们为无疾病的情况提供了QLT的第一个全面表征（2D）。由于潜在的经典渗透过渡将系统碎片碎裂成断开的真实空间群集，因此无序的定位可以出现在均质的2D LGT中，例如U（1）量子链接模型（QLM）。在渗透模型的基础上，我们通过详细研究通过级别间距统计数据和配置空间中的定位来表征U（1）QLM中QLT的QLT。我们主张存在两个制度 - 一种有效的大小群集有效地表现出色，结果自然地将其视为构型空间中的干扰现象，而另一个大型群集则以表面形式表现出来。作为一个核心结果，在后一种制度中，我们声称QLT等于经典的渗透过渡，因此是连续的。利用这种等价性，我们通过对渗透问题的有限尺寸缩放分析来确定QLT的普遍性类别和关键行为。
Disorder-free localization is a novel mechanism for ergodicity breaking which can occur in interacting quantum many-body systems such as lattice gauge theories (LGTs). While the nature of the quantum localization transition (QLT) is still debated for conventional many-body localization, here we provide the first comprehensive characterization of the QLT in two dimensions (2D) for a disorder-free case. Disorder-free localization can appear in homogeneous 2D LGTs such as the U(1) quantum link model (QLM) due to an underlying classical percolation transition fragmenting the system into disconnected real-space clusters. Building on the percolation model, we characterize the QLT in the U(1) QLM through a detailed study of the ergodicity properties of finite-size real-space clusters via level-spacing statistics and localization in configuration space. We argue for the presence of two regimes - one in which large finite-size clusters effectively behave non-ergodically, a result naturally accounted for as an interference phenomenon in configuration space and the other in which all large clusters behave ergodically. As one central result, in the latter regime we claim that the QLT is equivalent to the classical percolation transition and is hence continuous. Utilizing this equivalence we determine the universality class and critical behaviour of the QLT from a finite-size scaling analysis of the percolation problem.
