Measurement of diffraction effects in a focused pulse
Nine side-view snapshots of the intensity and color for a pulse that has over-filled a focusing lens (placed to the left of the picture; the light is propagating to the right). The images show the so-called fore-runner pulse that precedes the main component of the pulse and occurs only before the focus. These measurements had femtosecond temporal resolution and submicron spatial resolution simultaneously. This work was performed by grad student Pam Bowlan using the SEA TADPOLE technique that she developed. You can read more about it in the tutorial or in one of several papers that resulted from her work in the Trebino group.
In short, the Trebino group is the world's leading light-pulse-measurement group. Beginning with the Frequency-Resolved Optical Gating (FROG) technique--the first technique to measure the complete intensity and phase vs. time of an arbitrary pulse--and continuing through its more recent spatio-temporal measurement techniques, its techniques are the gold standards of light-pulse measurement.
If you have a challenging ultrafast light-measurement problem, consider collaborating with us!