Quasi-optical cavity dumping at millimetre wave frequencies

A thin silicon wafer illuminated by a Q-switched frequency-doubled Nd-YAG (yttrium aluminum garnet) laser is used as a very fast, ultra-low-loss, quasi-optical, photoconductive switch to cavity-dump a millimeter-wave open resonator. This novel scheme should provide short pulses at millimeter-wave frequencies with power gains of several hundred from conventional continuous-wave (CW) sources. The switch has extremely low insertion loss and can switch on timescales of a few nanoseconds. Potential applications are in high-resolution radar, plasma diagnostics, and pulsed electron spin resonance experiments.<
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