Transition Slow-Down by Rydberg Interaction of Neutral Atoms and a Fast Controlled-NOT Quantum Gate

Exploring controllable interactions lies at the heart of quantum science. Neutral Rydberg atoms provide a versatile route toward flexible interactions between single quanta. Previous efforts mainly focused on the excitation annihilation (EA) effect of the Rydberg blockade due to its robustness against interaction fluctuation. We study another effect of the Rydberg blockade, namely transition slow-down (TSD). In TSD, a ground-Rydberg cycling in one atom slows down a Rydberg-involved state transition of a nearby atom, which is in contrast to EA that annihilates a presumed state transition. TSD can lead to an accurate controlled-NOT (CNOT) gate with a submicrosecond duration of about 2 pi/ ? + by two pulses, where is a negligible transient time to implement a phase change in the pulse and ? is the Rydberg Rabi frequency. The speedy and accurate TSD-based CNOT gate makes neutral atoms comparable (superior) to superconducting (ion-trap) systems. Superscript/Subscript Available