Role of gate speed in high-fidelity robust Rydberg-blockade gates

Rydberg-mediated entangling operations in neutral-atom platforms operate in one of two limits: fast excitation to Rydberg states (diabatic gates) or via relatively slower intensity and

detuning ramps (adiabatic Rydberg dressing). Although these regimes are often treated separately, they are connected by a continuous parameter space defined by the detuning, Rabi frequency, and pulse intensity and frequency ramp rates. It is important to explore this regime particularly in the presence of shot-to-shot and high frequency intensity and phase noise in the Rydberg UV laser. We present an experimental and theoretical exploration of this adiabatic–diabatic crossover, using single-photon excitation of cesium atoms as a tunable platform. By varying the temporal shape and length of the excitation pulse intensity and frequency, we study how the two-qubit entanglement fidelity and robustness varies across regimes.