Long-lived revivals and real-space fragmentation in chains of multispecies Rydberg atoms

Abstract

Arrays of Rydberg atoms provide a powerful platform for exploring constrained quantum dynamics and nonergodic many-body phenomena. While most work has focused on single-species systems, multispecies architectures offer additional interaction channels and enable new forms of dynamical constraints. We study the nonequilibrium dynamics of one-dimensional dual-species Rydberg chains of Cs and Rb atoms with species-dependent van der Waals interactions. Using large-scale matrix product state simulations, we show that the competition between intraspecies repulsion and interspecies attraction induces dynamical fragmentation, marked by the coexistence of extended frozen regions and localized oscillatory sectors. The frozen regions act as emergent barriers that isolate and protect coherent dynamics. In the purely repulsive regime, we find that species-selective quenches drive spontaneous fragmentation, leading to dynamically disconnected regions with irregular revivals. These phenomena are robust across interaction regimes, revealing a universal mechanism for fragmentation and establishing multispecies Rydberg arrays as a versatile platform for exploring nonequilibrium quantum dynamics beyond single-species systems.