Multichannel quantum defect calculation of the phase lag in the coherent control of HI

Multichannel quantum defect theory (MQDT) is applied within a unified framework to compute the ionization and dissociation channel phases of HI. Our numerical results illustrate the mathematical origin of a channel phase within the MQDT formalism, and are consistent with the existing theory of this phenomenon, based on the collision formalism and with experimental measurements. The present study explains why previous MQDT calculations predicted that the channel phase vanishes identically.Peer reviewed: YesNRC publication: Ye

Experimental and theoretical studies of the channel phase in the coherent control of molecular processes

The source of the phase lag between different product channels in coherent control experiments is explored. It is shown theoretically that a structured continuum is required to obtain a non-zero channel phase. An isotope effect in the photoionization of HI and DI suggests a direct coupling between electronic and nuclear degrees of freedom. The occurrence of a channel phase is explained also in the context of multichannel quantum defect theory, resolving an earlier controversy.NRC publication: Ye