Magnetic Trapping of Long-Lived Cold Rydberg Atoms

We report on the trapping of long-lived strongly magnetized Rydberg atoms. ⁸⁵Rb atoms are laser cooled and collected in a superconducting magnetic trap with a strong bias field (2.9 T) and laser excited to Rydberg states. Collisions scatter a small fraction of the Rydberg atoms into long-lived high-angular momentum “guiding-center” Rydberg states, which are magnetically trapped. The Rydberg atomic cloud is examined using a time-delayed, position-sensitive probe. We observe magnetic trapping of these Rydberg atoms for times up to 200 ms. Oscillations of the Rydberg-atom cloud in the trap reveal an average magnetic moment of the trapped Rydberg atoms of ≈-8μ_B. These results provide guidance for other Rydberg-atom trapping schemes and illuminate a possible route for trapping antihydrogen.