Exact Treatment of the Stark Effect in Atomic Hydrogen

Abstract
A boundary-condition method is used to investigate the energy levels of atomic hydrogen in a uniform electric field. At low fields the misbehavior of trial eigensolutions in the nonclassical region enables one to obtain high-accuracy upper and lower bounds to the Stark shift. At higher fields the energy levels are treated as resonant states imbedded in a continuum. A modified WKB approach is used to obtain both the position and width of these resonances. Comparison is made with the usual perturbation-theory results.