ABSTRACT
A multipass amplifier configuration is described which has potential as a large aperture, high gain driver stage for fusion laser systems. We avoid the present limitations of large aperture switches by using an off-angle geometry that does not require an optical switch. The saturated gain characteristics of this multipass amplifier are optimized numerically. Three potential problems are investigated experimentally, self-lasing, output beam quality, and amplified spontaneous emission output. The results indicate comparable cost for comparable performance to a linear chain, with some operational advantage for the multipass driver stage.
ABSTRACT
The design and performance of an avalanche transistor switchout are described. The device selects a single pulse from a train of cw or Q-switched mode-locked pulses and introduces less than +/-1% amplitude variation in the selected pulse. The prepulse rejection ratio exceeds 10(7), and a lifetime of greater than 10(7) shots has been achieved.