PICOSECOND PHOTOCONDUCTIVE SAMPLING WITH NANOSECOND CARRIER LIFETIMES USING AN INTEGRATED INDUCTIVE LOOP

A noninvasive, photoconductive sampling technique, which does not require short-lifetime material to achieve picosecond temporal resolution, is demonstrated. The technique relies on electromagnetic coupling to generate the time derivative of the signal of interest in a separate sampling circuit. A slow photoconductive device in the sampling circuit integrates the coupled signal to produce the desired wave form. A 5-ps sampling response (limited only by circuit parasitics) was measured on GaAs with a lifetime of 1 ns by coupling to a small conducting loop.© 1995 American Institute of Physics.