Abstract
The production of very-high- (–500) strontium Rydberg atoms is explored using a crossed-laser-atom-beam geometry. and states are created by two-photon excitation via the intermediate state using radiation with wavelengths of 461 and 413 nm. Rydberg atom densities as high as cm have been achieved, sufficient that Rydberg-Rydberg interactions can become important. The isotope shifts in the Rydberg series limits are determined by tuning the 461-nm light to preferentially excite the different strontium isotopes. Photoexcitation in the presence of an applied electric field is examined. The initially quadratic Stark shift of the and states becomes near-linear at higher fields and the possible use of states to create strongly polarized, quasi-one-dimensional electronic states in strontium is discussed. The data are analyzed with the aid of a two-active-electron (TAE) approximation. The two-electron Hamiltonian, within which the Sr core is represented by a semi-empirical potential, is numerically diagonalized allowing the calculation of the energies of high- Rydberg states and their photoexcitation probabilities.
1 More- Received 1 July 2013
DOI:https://doi.org/10.1103/PhysRevA.88.043430
©2013 American Physical Society