title: Signatures and control of strong-field dynamics in a complex system.
abstract: Controlling chemical reactions by light, i.e., the selective making and breaking of chemical bonds in a desired way with strong-field lasers, is a long-held dream in science. An essential step toward achieving this goal is to understand the interactions of atomic and molecular systems with intense laser light. The main focus of experiments that were performed thus far was on quantum-state population changes. Phase-shaped laser pulses were used to control the population of final states, also, by making use of quantum interference of different pathways. However, the quantum-mechanical phase of these final states, governing the system's response and thus the subsequent temporal evolution and dynamics of the system, was not systematically analyzed. Here, we demonstrate a generalized phase-control concept for complex systems in the liquid phase. In this scheme, the intensity of a control laser pulse acts as a control knob to manipulate the quantum-mechanical phase evolution of excited states. This control manifests itself in the phase of the molecule's dipole response accessible via its absorption spectrum. As reported here, the shape of a broad molecular absorption band is significantly modified for laser pulse intensities ranging from the weak perturbative to the strong-field regime. This generalized phase-control concept provides a powerful tool to interpret and understand the strong-field dynamics and control of large molecules in external pulsed laser fields.
authors.affiliation: Max-Planck Institute for Nuclear Physics, 69117 Heidelberg, Germany; tpfeifer@mpi-hd.mpg.de kmeyer@mpi-hd.mpg.de.
authors.forename: Kristina
authors.initials: K
authors.lastname: Meyer
authors.affiliation: Max-Planck Institute for Nuclear Physics, 69117 Heidelberg, Germany; School of Nuclear Science and Technology, Lanzhou University, 730000 Lanzhou, China;
authors.forename: Zuoye
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Max-Planck Institute for Nuclear Physics, 69117 Heidelberg, Germany;
authors.forename: Niklas
authors.initials: N
authors.lastname: Müller
authors.affiliation: Interdisciplinary Center for Scientific Computing, Universität Heidelberg, 69120 Heidelberg, Germany;
authors.forename: Jan-Michael
authors.initials: JM
authors.lastname: Mewes
authors.affiliation: Interdisciplinary Center for Scientific Computing, Universität Heidelberg, 69120 Heidelberg, Germany;
authors.forename: Andreas
authors.initials: A
authors.lastname: Dreuw
authors.affiliation: Physikalisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany;
authors.forename: Tiago
authors.initials: T
authors.lastname: Buckup
authors.affiliation: Physikalisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany;
authors.forename: Marcus
authors.initials: M
authors.lastname: Motzkus
authors.affiliation: Max-Planck Institute for Nuclear Physics, 69117 Heidelberg, Germany; Center for Quantum Dynamics, Universität Heidelberg, 69120 Heidelberg, Germany tpfeifer@mpi-hd.mpg.de kmeyer@mpi-hd.mpg.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pfeifer
keywords: complex molecules; liquid phase; phase control; transient absorption spectroscopy