Multi-exciton states in flexible Rydberg aggregates

Abstract

Flexible Rydberg aggregates, assemblies of highly excited atoms, provide a platform to investigate quantum phenomena like energy transport and conical intersections. This can be achieved by doping the aggregate with an excitation, an excited state that is energetically higher but close to the primary Rydberg state, which results in the resonant dipole-dipole interaction becoming dominant. Consequently, the excitation is delocalized throughout the aggregate leading to the creation of exciton states. The properties of excitons have been studied for aggregates with a single excitation only. We follow up on previous results and add a second excitation to the system. Here, we demonstrate that most biexciton states for a dislocated chain at one end, a chain with equal spacing between atoms except for the last two, can be expressed as products of single exciton states. Moreover, we present the atomic trajectories for each biexciton state and we show that non-adiabatic effects are quite prominent in exible chains of Rydberg atoms. Finally, we analyze the interaction between two excitation pulses based on the initial biexciton state and the presence of a dislocation, then we show some cases where a transmission switch behavior is observable. Our ndings further enhance the range at which exible Rydberg aggregates can be used to model chemical quantum processes that take place in light harvesting molecules and molecular aggregates. Furthermore, the transmission switch behavior opens the possibility of using Rydberg aggregates in quantum information processing.