Microwave Trapped Plasma Devices Observed on a 35 GHz Sampling Oscilloscope

Optoelectronic switches have been built to generate and sample 100 volt pulses in 10 ps. This gives a unique opportunity to observe avalanche processes in X-band Trapatt diodes which are driven well above breakdown. The expected behaviour of such Trapatt diodes in a resistive npn-oscillatory circuit is reviewed for a step voltage drive and also for an optical pulse input. It is concluded that 10 ps switches are essential to provide a sufficiently fast ramp voltage to initiate the trapped plasma and to sample adequately the subsequent collapse of voltage across the diode. Progress in this technique of optoelectronic sampling is reviewed.