Localization and Criticality in Antiblockaded Two-Dimensional Rydberg Atom Arrays

Fangli Liu, Zhi-Cheng Yang, Przemyslaw Bienias, Thomas Iadecola, and Alexey V. Gorshkov

Phys. Rev. Lett. 128, 013603 – Published 6 January 2022

Abstract

Controllable Rydberg atom arrays have provided new insights into fundamental properties of quantum matter both in and out of equilibrium. In this work, we study the effect of experimentally relevant positional disorder on Rydberg atoms trapped in a 2D square lattice under antiblockade (facilitation) conditions. We show that the facilitation conditions lead the connectivity graph of a particular subspace of the full Hilbert space to form a 2D Lieb lattice, which features a singular flat band. Remarkably, we find three distinct regimes as the disorder strength is varied: a critical regime, a delocalized but nonergodic regime, and a regime with a disorder-induced flat band. The critical regime’s existence depends crucially upon the singular flat band in our model, and is absent in any 1D array or ladder system. We propose to use quench dynamics to probe the three different regimes experimentally.

Received 18 December 2020
Revised 30 October 2021
Accepted 13 December 2021

DOI:https://doi.org/10.1103/PhysRevLett.128.013603

Physics Subject Headings (PhySH)

Cold atoms & matter waves Localization Quantum criticality Quantum quench

2-dimensional systems Atomic gases Rydberg atoms & molecules

Lattice models in condensed matter

Atomic, Molecular & OpticalCondensed Matter, Materials & Applied PhysicsStatistical Physics & Thermodynamics

Authors & Affiliations

Fangli Liu¹, Zhi-Cheng Yang ¹, Przemyslaw Bienias¹, Thomas Iadecola², and Alexey V. Gorshkov ¹

¹Joint Quantum Institute and Joint Center for Quantum Information and Computer Science, NIST/University of Maryland, College Park, Maryland 20742, USA
²Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA