Experimental study of power gain in an inductive energy pulsed power system with an optically activated semiconductor opening switch

Summary form only given. An experiment was conducted that demonstrates a substantial amount of power gain achieved in a pulsed power system consisting of a current charged transmission line and an optically activated semiconductor switch. A specially tailored 1.06-μm laser light pulse for which the risetime is ~200 ns, the falltime is ~10 ns, and the total laser pulse energy is ~2 mJ was employed to multiply the charging current, resulting in a power gain of as high as 13. The best result was obtained with a p-i-n diode configuration for the GaAs switch: the dimension is 6×6×0.5 mm, the carrier recombination time is 2 ns, gold evaporated electrodes are of a ring shape on the p-region side (which allows light transmission into the switch material), and there is a flat electrode on the n-region side. The on-resistance (while the light is illuminated) and off-resistance of the switch were inferred from measured output waveforms using transmission line theory and found to be 0.5 Ω and 230 Ω, respectively. The maximum operating voltage scales with the thickness of the switches. It was observed, for all switches tested, that the output voltage does not scale linearly with the charging current: the power gain drops slowly as the charging current increases