Many-body Localization From Dynamical Gauge Fields
Zhiyuan Yao (么志远) 博士后 清华大学
摘要：Gauge theory not only plays a central role in describing fundamental interactions in nature but also often emerges as the low-energy effective theory of various condensed matter systems. Starting from about a decade ago, simulating synthetic gauge fields has also become a main research topic in cold-atom physics. Inspired by a recent experiment [Nat. Phys. 15, 1168 (2019)] that realized a dynamical gauge system with a Z2 gauge symmetry in a double-well potential, we propose a method to generalize this model from a single double well to a one-dimensional chain. We show that although there are no disordered potentials in the original model, the phenomenon of many-body localization can occur. The key ingredient is that local gauge charges play the role of different disorder configurations, which becomes clear after exactly mapping our model to a transverse Ising model in a random longitudinal field. We provide extensive numerical evidence to show that both the ergodic regime and the many-body localized regime exist in this model.