Coherent dynamics in a five-level atomic system

Abstract

The coherent control of multi-partite quantum systems presents one of the central prerequisites in state-of-the-art quantum information processing. With the added benefit of inherent high-fidelity detection capability, atomic quantum systems in high-energy internal states, such as metastable noble gas atoms, promote themselves as ideal candidates for advancing quantum science in fundamental aspects and technological applications. Using laser-cooled neon atoms in the metastable $^3$P$_2$ state of state $1s^2 2s^2 2p^5 3s$ (LS-coupling notation) (Racah notation: $^2P_{3/2}\,3s[3/2]_2$) with five $m_F$-sublevels, experimental methods for the preparation of all Zeeman sublevels |m_J> = |+2>, |+1>, |0>, |-1>, |-2> as well as the coherent control of superposition states in the five-level system |+2> ... |-2>, in the three-level system |+2>, |+1>, |0>, and in the two-level system |+2>, |+1> are presented. The methods are based on optimized radio frequency and laser pulse sequences. The state evolution is described with a simple, semiclassical model. The coherence properties of the prepared states are studied using Ramsey and spin echo measurements.