Laser-triggered Vacuum Switch Research Articles

Firing characteristics of a low-jitter miniature laser-triggered vacuum switch

A miniature laser-triggered high-voltage vacuum switch with a fused KCl and Ni cathode is discussed. The switch uses metal-ceramic construction with a sapphire window in the anode to allow the laser beam to strike the cathode surface. Reliable triggering is achieved with only 20 mu J of laser energy. The switch was operated with a gap voltage ranging from 500 V to 3 kV, with switching currents up to a 5 kA peak. Switch life greater than 1000 shots without performance degradation has been observed on 50 prototype devices. The function time of the switch varies from 10+or-1 ns at 3 kV to 100+or-50 ns at 500 V.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A model for the operation of a laser-triggered vacuum low-inductance switch

A new model for the operation of a laser-triggered vacuum switch utilizing a composite target pellet in the cathode is given along with supporting experimental results. It is shown that two separate mechanisms are responsible for the operation of the switch, namely, a thermal mechanism for the initial current flow and an ion regeneration mechanism for the current buildup. The current buildup is strongly dependent upon geometry, as is evident from the experiments with 3- and 1-mm apertures in the anode. The jitter time is primarily determined during current buildup and nearly independent of the laser energy. An ion regeneration mechanism is consistent with the experimental data for current buildup, and a thermal mechanism is consistent with the initial generation of current.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Low-jitter laser-triggered vacuum switch using a composite target

A laser-triggered high-voltage vacuum switch with a composite KCl/Ti target pellet is described. The switch triggers reliably for 532-nm laser input energies of 20 mu J corresponding to a peak irradiance of 1 MW/cm/sup 2/. Jitter times of less than +or-15 ns and delay times of less than 100 ns are observed. Several experiments were performed to explore the operation of the switch. It was found that the amount of energy needed to trigger the switch and the jitter time was strongly dependent on the position of the pellet relative to the cathode. It is noted that the mechanism responsible for the operation of the switch is not completely understood. >