Amplified spontaneous emission and nanosecond pulse amplification in large-aperture electron-beam-pumped KrF amplifiers

摘要

The experiments have been performed at 100-J-class GARPUN KrF laser installation, which consists of 20-ns discharge-pumped master oscillator and two stages of e-beam-pumped amplifiers with gain volumes of 10x10x100 cm and 16 x 18 x 100 cm. Gain and absorption coefficients were measured in a single-pass scheme, while intrinsic efficiency of about 12% was demonstrated in the saturated double-pass amplification. They were compared with numerical simulations. A numerical code solved a set of simultaneous self-consistent kinetic equations together with amplification of laser radiation and spontaneous emission in large-aperture KrF lasers. Being verified with the experimental data the code was used to forecast the parameters of IFE-scale KrF amplifiers.