Mrw. Bellermann et al., RESONANT, ELLIPTIC-POLARIZATION CONTROL OF MICROWAVE IONIZATION OF HYDROGEN-ATOMS, Physical review letters, 78(20), 1997, pp. 3840-3843
For certain ranges of the principal quantum number n(0) much greater t
han 1 a few units wide, ionization of hydrogen atoms by a 9.904 GHz el
ectric field is observed to be extremely sensitive to elliptical polar
ization. Classical 3D Monte Carlo calculations quantitatively reproduc
e the experimental data. Classical theory shows that the observed sens
itivity to elliptical polarization is a resonant effect in this strong
ly driven quantal system. The resonant dynamics provides a mechanism f
or controlling the ionization.