KRF AMPLIFIER DESIGN ISSUES AND APPLICATION TO INERTIAL CONFINEMENT FUSION SYSTEM-DESIGN

Los Alamos National Laboratory has assembled an array of experimental and theoretical tools to optimize amplifier design for future single-p ulse KrF lasers. The next opportunity to exercise these tools is with the design of the second-generation NIKE system under construction at the Naval Research Laboratory with the collaboration of Los Alamos Nat ional Laboratory. Major issues include laser physics (energy extractio n in large modules with amplified spontaneous emission) and diode perf ormance and efficiency. Low cost is increasingly important for larger future KrF single-pulse systems (low cost and high efficiency is impor tant for larger repetitively pulsed applications such as electric powe r production). In this article, we present our approach to amplifier s caling and discuss the more important design considerations for large single-pulse KrF amplifiers. We point out where improvements in the fu ndamental database for KrF amplifiers could lead to increased confiden ce in performance predictions for large amplifiers and address the cur rently unresolved issues of anomalous absorption near line center and the possibility of diode instabilities for low-impedance designs. Los Alamos has applied these amplifier design tools to the conceptual desi gn of a 100-kJ Laser Target Test Facility and a 3-MJ Laboratory Microf usion Facility.