title: Towards optimal control with shaped soft-x-ray light.
abstract: We demonstrate the first example of a closed-loop adaptive control experiment in the soft-x-ray spectral region. The branching ratio of the dissociative photoionization of sulfur hexafluoride (SF(6)) can be maximized and minimized by applying tailored soft-x-ray femtosecond light fields. The spectrally shaped coherent soft-x-ray pulses are produced by high-harmonic generation driven by phase-shaped femtosecond laser pulses. The stability of the shaped high-harmonic output is high enough to perform adaptive control experiments, albeit its strong nonlinear dependence on the driving laser pulse shape. This experiment opens the door to the application of pulse-shaping and coherent-control techniques in the soft-x-ray range.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pfeifer
authors.forename: Robert
authors.initials: R
authors.lastname: Spitzenpfeil
authors.forename: Dominik
authors.initials: D
authors.lastname: Walter
authors.forename: Carsten
authors.initials: C
authors.lastname: Winterfeldt
authors.forename: Frank
authors.initials: F
authors.lastname: Dimler
authors.forename: Gustav
authors.initials: G
authors.lastname: Gerber
authors.forename: Christian
authors.initials: C
authors.lastname: Spielmann