Pulse-shaper-assisted spatio-temporal ultrashort pulse characterisation

Here, we present a robust and straightforward implementation of spatio-temporal measurement by combining a Shack-Hartmann wavefront sensor with the Dazzler acousto-optic programmable dispersive filter from Fastlite. The Dazzler selects spectral slices of the pulse. The spatial phase of each slice is measured using a Shack-Hartmann wavefront sensor. Then, the Dazzler is operated as a bFROG [5] to retrieve the spectral phase and amplitude at a single spatial position. The wavefronts at each frequency may then be related by this spectral phase, providing a three-dimensional measurement of the phase.