Essential Conditions for Dynamic Interference

We develop general quantitative criteria for dynamic interference, a manifestation of a double-slit interference in time which should be realizable with brilliant state-of-the-art high-frequency laser sources. Our analysis reveals that the observation of dynamic interference hinges upon maximizing the difference between the dynamic polarization of the initial bound and the final continuum states of the electron during the light pulse while keeping depletion of the initial state small. These two properties, Stark shift and depletion, can be determined from electronic structure calculations avoiding expensive propagation in time. Confirmed by numerical results, we predict that this is impossible for the hydrogen ground state but feasible for excited states; this has been exemplified for the case of the hydrogen 2p state.