Optical excitation of atomic sodium Rydberg states in electric field

Kriti Batra, Vinod Prasad, Man Mohan

Jean Vialle

This paper presents a new method for studying the ionization of highly excited atomic Rydberg states by a static electric field. This method is especially well adapted when several ionization thresholds appear for a given atomic level. The advantages of the method are illustrated on the 20d state of Na.

Annemieke Kips

Eric J. Korevaar, Michael G. Littman

The excitation spectrum for Rydberg states near n=11 of atomic sodium in crossed electric and magnetic fields has been recorded. The theoretical analysis of the spectroscopic data reveals degeneracies among some sublevels even though different sublevels are mixed by the external fields. The degeneracies are traced to a dynamical symmetry that is characteristic of the Coulomb potential.

Richard R. Freeman, Theodore W. Ducas, Michael G. Littman +1 more

Robert W. Boyd, Daniel J. Gauthier, Jerzy S. Krasiński +1 more

It has recently been shown1 that extremely large values of the second-order nonlinear suceptibility can be obtained through use of Rydberg atomic states perturbed by an external electric field.2 In these experiments a value of χ(2) = 10-9 esu was obtained using a sodium vapor of number density ~1014 atoms cm-3 and a dc electric field of magnitude 1 kV/cm. One laser was tuned close to the sodium D2 resonance line while a second laser completed the two-photon resonance with a Rydberg state. A strong coherent UV beam at the sum frequency was generated in the forward direction. The splitting of the highly excited atomic levels induced by the external electric field created a broad region of overlapping levels, leading to continuous tunability. This technique can be applied to any system displaying a Rydberg series, and should be capable of producing coherent, tunable radiation in the extreme ultraviolet.