Photoemission sampling measurements of a dispersing voltage pulse traveling on a transmission line

The newly developed method of photoemission sampling, based on the single-photon process, has been applied to measure the dispersion of a picosecond voltage pulse traveling on a transmission line. The dispersion of the propagating pulse is clearly revealed in the spectra which show signal rise times of about 17 ps at 2 mm away from the pulse generating switch, and change into rise times of about 30 ps at 1.5 mm further away. The time resolution of the measurements is better than 7 ps. Therefore, photoemission sampling with picosecond laser pulses permits the measurement of changes in signal waveforms at arbitrary points of a transmission line and for arbitrary substrate materials with sufficient time resolution.