Spatially encoded, single-shot ultrafast spectroscopies

We analyze the time-resolution constraints for two single-shot, time-resolved femtosecond spectroscopic techniques, an excite–probe method, and a transient-grating method. For pulse lengths of tens of femtoseconds, the former technique is shown to provide pulse-length-limited resolution for samples as much as hundreds of micrometers thick. The latter technique is shown to provide nearly pulse-length-limited resolution under a variety of conditions, independent of the sample thickness.