title: Dynamics of solvation and desolvation of rubidium attached to He nanodroplets.
abstract: The real-time dynamics of photoexcited and photoionized rubidium (Rb) atoms attached to helium (He) nanodroplets is studied by femtosecond pump-probe mass spectrometry. While excited Rb atoms in the perturbed 6p-state (Rb*) desorb off the He droplets, Rb(+) photoions tend to sink into the droplet interior when created near the droplet surface. The transition from Rb(+) solvation to full Rb* desorption is found to occur at a delay time τ ∼ 600 fs for Rb* in the 6pΣ-state and τ ∼ 1200 fs for the 6pΠ-state. Rb(+)He ions are found to be created by directly exciting bound Rb*He exciplex states as well as by populating bound Rb(+)He-states in a photoassociative ionization process.
authors.affiliation: Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany.
authors.forename: J
authors.initials: J
authors.lastname: von Vangerow
authors.affiliation: Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany.
authors.forename: O
authors.initials: O
authors.lastname: John
authors.affiliation: Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Stienkemeier
authors.affiliation: Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Mudrich