Nonlinear resonance in the hydrogen atom

Abstract
The size and location of nonlinear-resonance zones, in the one-dimensional model microwave-driven hydrogen, are obtained numerically for the microwave field strengths and frequency used in experiments. Classical simulations show a high correlation between the widths of fractional resonances at the chaos border and the width of regions of suppressed ionization observed in experiments. Numerical evidence is given for the existence of quantum nonlinear resonances in microwave-driven hydrogen.