High Harmonic Generation
We are operating a dedicated laser laboratory to complement our steady-state investigations at BESSYII and other synchrotron radiation facilities and our time-resolved investigations at free-electron laser sources. One of the main applications in this lab is the use of femtosecond VUV photon pulses from high-order harmonic generation (HHG) of a Ti:Sapphire laser for photoelectron spectroscopy of gases, liquids and solids.
Figure 2: Schematic representation of the experimental setup with generation of the high-order harmonics in a gas cell, with VUV focusing and with time of flight electron and ion spectrometers. BS denotes the beamsplitter and λ/2 the lambda half plates in the pump and probe parts of the laser beam [taken from Wernet et al., Rev. Sci. Instrum. 82, 063114 (2011)].
Ph. Wernet, J. Gaudin, K. Godehusen, O. Schwarzkopf, W. Eberhardt, Femtosecond time-resolved photoelectron spectroscopy with a Vacuum-Ultraviolet photon source based on laser high-order harmonic generation, Rev. Sci. Instrum. 82, 063114 (2011).