Abstract
We experimentally observe the bond stretching time of one-photon and net-two-photon dissociation pathways of singly ionized molecules driven by a polarization-skewed femtosecond laser pulse. By measuring the angular distributions of the ejected photoelectron and nuclear fragments in coincidence, the cycle-changing polarization of the laser field enables us to clock the photon-ionization starting time and photon-dissociation stopping time, analogous to a stopwatch. After the single ionization of , our results show that the produced takes almost the same time in the one-photon and net-two-photon dissociation pathways to stretch to the internuclear distance of the one-photon coupled dipole-transition between the ground and excited electronic states. The spatiotemporal mapping character of the polarization-skewed laser field provides us a straightforward route to clock the ultrafast dynamics of molecules with sub-optical-cycle time resolution.
- Received 15 March 2019
- Revised 9 November 2019
DOI:https://doi.org/10.1103/PhysRevLett.123.233202
© 2019 American Physical Society