Ionization of xenon Rydberg atoms at surfaces

Abstract

Measurements of the ionization of the extreme red and blue states in high-lying Xe( n) Stark manifolds at a metal surface are reported. The data show that, despite their very different initial spatial characteristics, the extreme members of a given Stark manifold ionize at similar atom/surface separations. This is attributed to energy level shifts induced by the presence of the surface which lead to avoided crossings between states in adjacent n manifolds prior to ionization. These energy level shifts are examined using hydrogenic complex scaling theory.