Abstract

The quantum theory of atoms is based on a Hamiltonian which is just that of the classical Kepler theory of planetary orbits. In spite of this common foundation, the predictions of quantum theory ordinarily do not much resemble those of the classical theory. However, there are atomic states which do behave classically. We have excited and detected an atomic electron wave packet that is localized in the polar and azimuthal angles.¹ The wave packet is formed through the coherent superposition of Rydberg states of atomic sodium. The superposition is achieved by short-pulse optical excitation of the atom in the presence of a strong rf field. The wave packet is detected by dc field ionization. The ionization rate of such a wave packet depends on its angular localization (the angular width and orientation with respect to the dc field). A classical model of the ionization predicts this behavior.

© 1988 Optical Society of America