electron beam activated diamond switches have been constructed and operated. In an initial set of experiments the electron source consisted of a LaB$-6$/ photocathode illuminated by approximately 15 nanosecond pulses of 248 nm light from a KrF laser. The photocathode could be biased at voltage of 10 - 80 kV. The type IIa diamond wafer was 12 microns thick with top and bottom electrodes consisting of Ti/Pt/Au sputtered metallizations (unannealed). Limited by surface flashover across a 12 micron broken edge of the diamond wafer, pulses with a peak power at the kilowatt level into 50 ohms were generated. The output pulse duration was set by the electron beam duration or the round trip time in the charged transmission line, whichever was shorter. Measurement of the output pulse rise time was limited by the diagnostic oscilloscope resolution but was less than one nanosecond. It was observed that the output pulse amplitude reached the expected value only when the bombarding electron beam voltage was sufficiently large that carrier pairs were generated throughout the thickness of the diamond sample.
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