Attosecond velocity-map-imaging

Tunneling is a very fundamental phenomenon in quantum mechanics. The question of the duration of the tunneling process itself has been raised before. Experiments give different outcomes and different theories predict different tunneling times. In strong field physics tunneling time has been measured to amount to 12as with an error bar including zero tunneling delay. This thesis describes the extension of the attosecond angular streaking technique using a Velocity Map Imaging Spectrometer. The apparatus for strong field experiments in the attosecond regime has been designed for various strong-field experiments. It has been set up and tested in the course of this thesis. Angular streaking measurements are presented. The accessible intensity range for this class of experiments is extended to lower intensities and the measurement accuracy improved. In the previously examined intensity range a tunneling delay of 36as was measured, independently of the exact electrical field strength in the laser focus. For lower electrical field strengths, an increase of the delay time was measured. However, it is not entirely clear, whether the tunneling picture is still applicable in this regime.