The role of mass in the carrier-envelope phase effect for H2+ dissociation

The carrier-envelope phase (CEP) dependence of the dissociation of H-2(+) is studied with special emphasis on the role of the nuclear mass. We find that the total dissociation probability displays a CEP effect that grows with increasing mass, while the difference between dissociating to p+H and H+p displays an effect that shrinks. Insight into the physical processes involved is given by an analytic description that casts CEP effects as interferences between pathways requiring different numbers of photons.