Quantum interference and laser pulse phase effect on the photoionization rates of excited hydrogen atoms in the tunneling region

摘要

Using the generalized Keldysh theory, we investigate the quantum interference and the laser pulse phase effects by tunneling photoionization of an excited hydrogen atom. We assume that its initial state be a linear combination of 1s, 2s, 2p Stark-shifted atomic states. It is found that within the Keldysh approximation, quantum interference can take place among the 1s, 2s, and 2pz states, while this is not the case among 1s, 2s, 2pz and 2px, 2py, or 2px and 2py themselves. From the numerical calculations, we predict that the prominent destructive quantum interference takes place between 2s and 2pz atomic orbitals. In addition, we have found that in general, the laser pulse phase does not affect the individual photoionization rates while it does affect the quantum interference terms.