Stark manifolds of barium Rydberg states

Jacques Boulmer, Pierre Camus, Jean-Marie Lecomte +1 more

Herbert H. Rinneberg, Jörg Neukammer, Andreas Sebastian Konig +5 more

Wolfgang Sandner, Kambiz Ali Safinya, F. Gounand +1 more

Robert R. Lewis, Araceli Góngora

Haifeng Yang, Wei Jia Gao, Hong Cheng +2 more

We present observations of Stark spectra of barium in highly excited Rydberg states in the energy region around n = 35. The one-photon excitation concerns the π transition. The observed Stark spectra at electric fields ranging from 0 to 60 V·cm −1 are well explained by the diagonalization of the Hamiltonian incorporating the core effects. From the Stark maps, the anti-crossings between energy levels are identified experimentally and theoretically. The time of flight spectra at the specified Stark states are recorded, where the deceleration and acceleration of barium atoms are observed. This is very consistent with the prediction derived from the Stark maps from the point of view of energy conservation.

Wang Lei, Quan Wei, Shen Li +5 more

We observe strong energy-dependent quantum defects in the scaled-energy Stark spectra for | M | = 1 Rydberg states of barium atoms at three scaled energies: ε = –2.000, ε = –2.500 and ε = –3.000. In an attempt to explain the observations, theoretical calculations of closed orbit theory based on a model potential including core effect are performed for non-hydrogenic atoms. While such a potential has been uniformly successful for alkali atoms with a single valence electron, it fails to match experimental results for barium atoms in the 6snp Rydberg states with two valence electrons. Our study points out that this discrepancy is due to the strong perturbation from the 5d8p state, which voids the simple approximation for constant quantum defects of principle quantum number n.