Excitation of an atomic electron to a coherent superposition of macroscopically distinct states

An atomic electron is prepared in a state closely analogous to Schrodinger's coherent superposition of ''live cat'' and ''dead cat.'' The electronic state is a coherent superposition of two spatially localized wave packets separated by approximately 0.4 mu m at the opposite extremes of a Kepler orbit. State-selective ionization is used to verify that only every other atomic level is populated in the ''cat state,'' and a Ramsey fringe measurement is used to verify the coherence of the superposition.