title: Quantum Mechanical Wave Packet Dynamics at a Conical Intersection with Strong Vibrational Dissipation.
abstract: We derive a reduced model for the nonadiabatic quantum dynamics of an electronic wave packet moving through a conical intersection in the presence of strong vibrational damping. Starting from the dissipative two-state two-model model, we transform the tuning and the coupling mode to the bath. The resulting quantum two-state model with two highly structured environments is solved numerically exactly in the regime of strong vibrational damping. We find negative cross peaks in the ultrafast optical 2D spectra as clear signatures of the conical intersection. They arise from secondary excitations of the wave packet after having passed through the photophysical energy funnel. This feature is in agreement with recent transient absorption measurements of rhodopsin.
authors.affiliation: I. Institut für Theoretische Physik, Universität Hamburg , Jungiusstraße 9, 20355 Hamburg, Germany.|Max Planck-Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149, 22761 Hamburg, Germany.|The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: Hong-Guang
authors.initials: HG
authors.lastname: Duan
authors.affiliation: I. Institut für Theoretische Physik, Universität Hamburg , Jungiusstraße 9, 20355 Hamburg, Germany.|The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Thorwart