Laser Spectroscopy of Highly Excited Hydrogen Atoms in Strong Magnetic Fields

Abstract

In the physics of highly excited atoms around the ionization limit in external electric and magnetic fields [1], that is under strong field mixing [2] conditions, the H atom naturally plays a fundamental role. However, while the atom has served as basis for extensive theoretical studies, little experimental work has been performed with it. Electric field experiments have been carried out recently [3,4,5] showing agreement with well developed theory [1,2,6], as must be expected on account of the separability of the nonrelativistic problem. No experiments are known with H in magnetic fields, except most recent ones [4], which also include the first observation of quasi-Landau resonances above the ionization threshold. Different from the electric field case, the H atom with diamagnetic, interaction described in the simplest form by the Hamiltonian H ^coul_diam = −1/r + 1/8 α ²B²r² sin² Θ, still presents basic, open problems, theoretically and diam experimentally.