The fate of quantum many-body scars in the presence of disorder

TL;DR

This paper investigates the stability of quantum many-body scars in disordered Rydberg atom systems, revealing their robustness and the persistence of oscillation frequencies despite disorder-induced decay in amplitude.

Contribution

It provides a combined numerical and analytical study showing that quantum many-body scars remain stable under disorder, with oscillation frequencies unaffected and additional scar resonances emerging.

Findings

Oscillation amplitudes decay with increasing disorder

Oscillation frequencies remain constant despite disorder

Disorder introduces new scar resonances that enhance oscillations

Abstract

Experiments performed on strongly interacting Rydberg atoms have revealed surprising persistent oscillations of local observables. These oscillations have been attributed to a special set of non-ergodic states, referred to as quantum many-body scars. Although a significant amount of research has been invested to understand these special states, it has remained unclear how stable scar states are against disorder. We address this question by studying numerically and analytically the magnetization and spatio-temporal correlators of a model of interacting Rydberg atoms in the presence of disorder. While the oscillation amplitudes of these observables decay with time as the disorder strength is increased, their oscillation frequency remains remarkably constant. We show that this stability stems from resonances in the disordered spectrum that are approximately centered at the same scar energies of the clean system. We also find that multiple additional sets of scar resonances become accessible due to the presence of disorder and further enhance the oscillation amplitudes. Our results show the robustness of non-ergodic dynamics in scar systems, and opens the door to understanding the behavior of experimentally realistic systems.