Design of disk laser amplifiers for laser fusion applications

Large laser systems for fusion research employ disk laser amplifiers at the output of each amplifier chain owing to the superior nonlinear performance of large-aperture (d > 10-cm) disk amplifiers over rod amplifiers of the same aperture. This superior performance arises from three sources: (1) generally higher attainable gain coefficients; (2) reduction in beam intensity inside the Brewster’s angle disks; and (3) the air spaces between successive disks permitting diffraction to diverge small-scale self-focusing filaments.