Modeling Coherent Laser Excitation of Mixed Three-Atom States Near Förster Resonance

State-mixing interactions can compromise the effectiveness of the Rydberg excitation blockade near Förster resonance.  We detect a significant number of atoms in dipole-coupled product states immediately after laser excitation to a target Rydberg state.  Under certain conditions, this is due to excitation of mixed three-atom states.   We use a rotary echo technique to demonstrate the coherence of the evolution of these three-atom states.  In this poster, we describe a Monte Carlo simulation that allows us to interpret our rotary echo data.  We also explain a theoretical model for laser excitation in a coupled three-atom basis,¹ and show that it describes our data well for short pulse durations and low Rabi frequency.

 ¹ PRL 102, 013004 (2009)