Entangling atomic spins and Jaynes-Cummings ladder with a Rydberg-Dressed interaction.
Grant W. Biedermann
We demonstrate a Rydberg-dressed ground-state blockade that provides a strong tunable interaction energy (~1 MHz), nearly 4 orders of magnitude larger than that in ultra cold collisions, between spins of individually trapped cesium atoms.With this interaction we directly produce Bell-state entanglement between two atoms with a fidelity ≥ 81(2)%, excluding atom loss events, and ≥ 60(3)% when loss is included [1].Our method is based on a Rydberg-dressed spin-flip blockade which allows single-step, direct entanglement of long-lived ground (clock) states.For the Bell-state entanglement generation, the probability remains entirely in the Rydbergdressed ground state, freeing the approach from the experimental burden of coherently exciting optical transitions to and from the Rydberg states.In principle Rydberg-dressed atoms are more insensitive to various decoherence mechanisms and lead to a better quantum control fidelity [2].In addition, we observed Jaynes-Cummings (JC) ladder and its nonlinearity of a Rydbergdressed atomic system.This nonlinearity induced by the Rydberg-dressed spin-flip blockade and the symmetric coupling between a Rydberg atom and atomic ensembles in the ground state, and this differentiates single and two microwave photon excitations from Rydberg-dressed state atoms.
•Mar 7, 2017•0 citations