Persistent non-Gaussian correlations in out-of-equilibrium Rydberg atom arrays

Gaussian correlations emerge in a large class of many-body quantum systems quenched out of equilibrium, as demonstrated in recent experiments on coupled one-dimensional superfluids [Schweigler et al., Nat. Phys. 17, 559 (2021)]. Here we present a mechanism by which an initial state of a Rydberg atom array can retain persistent non-Gaussian correlations following a global quench. This mechanism is based on an effective kinetic blockade rooted in the ground state symmetry of the system, which prevents thermalizing dynamics under the quench Hamiltonian. We propose how to observe this effect with Rydberg atom experiments and we demonstrate its resilience regarding several types of experimental error. These long-lived non-Gaussian states may have practical applications as quantum memories or stable resources for quantum information protocols due to the protected non-Gaussianity away from equilibrium.