Interplay of localization and topology in disordered dimerized array of Rydberg atoms

TL;DR

This study explores how positional disorder and dimerization influence localization and topological properties in a disordered Rydberg atom array, revealing a unique localized phase and the persistence of SPT states across energies.

Contribution

It introduces a tunable model of disordered dimerized Rydberg arrays and uncovers a novel localized phase distinct from MBL, along with the presence of extensive SPT states.

Findings

Disorder and dimerization induce a unique localized phase.

The localized phase differs from standard many-body localization.

A significant fraction of the spectrum hosts symmetry-protected topological states.

Abstract

Rydberg tweezer arrays provide a platform for realizing spin-1/2 Hamiltonians with long-range tunneling that decays as a power law with distance. We numerically investigate the effects of positional disorder and dimerization on the properties of excited states in such a one-dimensional system. Our model allows for continuous tuning of both the dimerization pattern and the disorder strength. Within the parameter space constrained by our geometry, we show that both mechanisms lead to a localized phase that does not resemble standard MBL. This phase can be understood as an ensemble of distinct Hilbert space fragmented realizations induced by small inter-spin separations. As dimerization is commonly associated with Symmetry Protected Topological (SPT) physics, we also examine the SPT states across the entire energy spectrum. Despite a partial spin-glass order, we argue that the system hosts an extensive fraction of SPT states.