Publications Details
The use of optically triggered, high gain GaAs switches for UWB pulse generation
A high peak power impulse pulser that is controlled with high gain, optically triggered GaAs Photoconductive Semiconductor Switches (PCSS) has been constructed and tested. The system has a short 50 {Omega} line that is charged to 100 kV and discharged through the switch when the switch is triggered with as little as 90 nJ of laser energy. The laser that is used is a small laser diode array whose output is delivered through a fiber to the switch. The current in the system ranges from 1 kA (with one laser) to 1.3 kA (with two) and the pulse widths are 1.9 and 1.4 ns, respectively. The peak power and the energy delivered to the load are 50 MW to 84 MW and 95 NJ to 120 mJ for one or two lasers. The small trigger energy and switch jitter are due to a high gain switching mechanism in GaAs. This experiment also shows a relationship between the rise time of the voltage across the switch and the required trigger energy and switch jitter.