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The production of high-n, n ∼ 300, quasi-one-dimensional (quasi-1D) strontium Rydberg atoms through two-photon excitation of selected extreme Stark states in the presence of a weak dc field is examined using a crossed laser-atom beam geometry. The dipolar polarization of the electron wave function in the product states is probed using two independent techniques. The experimental data are analyzed with a classical trajectory Monte Carlo simulation employing initial ensembles that are obtained with the aid of quantum calculations based on a two-active-electron model. Comparisons between theory and experiment highlight different characteristics of the product quasi-1D states, in particular, their large permanent dipole moments, ∼1.0 to 1.2n 2 ea 0 , where e is the electronic charge and a 0 is the Bohr radius. Such states can be engineered using pulsed electric fields to create a wide variety of target states.

Nondispersive localized Trojan wave packets with n i $ 305 moving in near-circular Bohr-like orbits are created and transported to localized near-circular Trojan states of higher n, n f $ 600, by driving with a linearly polarized sinusoidal electric field whose period is slowly increased. The protocol is remarkably efficient with over 80% of the initial atoms being transferred to the higher n states, a result confirmed by classical trajectory Monte Carlo simulations.

The efficient production of very-high-n, n ∼ 300, quasi-one-dimensional (quasi-1D) strontium Rydberg atoms through three-photon excitation of extreme Stark states in the presence of a weak dc field is demonstrated using a crossed laser-atom beam geometry. Strongly polarized quasi-1D states with large permanent dipole moments ∼1.2n 2 a.u. can be created in the beam at densities (∼10 6 cm −3) where dipole blockade effects should become important. A further advantage of three-photon excitation is that the product F states are sensitive to the presence of external fields, allowing stray fields to be reduced to very small values. The experimental data are analyzed using quantum calculations based on a two-active-electron model together with classical trajectory Monte Carlo simulations. These allow determination of the atomic dipole moments and confirm that stray fields can be reduced to 25 μV cm −1 .

We demonstrate experimentally and theoretically that the spatial distribution of high angular momentum Rydberg wave packets, and thus off-diagonal elements of the density matrix, can be probed in detail through extraction of the moments of the position distribution y λ (λ = 1, 2) from quantum beat revivals. Detailed knowledge of the position distribution allows precise manipulation of the wave packet which is demonstrated by the control of its n distribution.