MODE-LOCKING IN SOLID-STATE LASERS BY SEL F-FOCUSING

The self-consistent ABCD method is used to analyse the fundamental eig enmode of a four-mirror cavity with an active element and an aperture. Practical titanium-activated lasers with Kerr-lens mode locking are c onsidered. The ranges of the cavity parameters are found in which the diffraction losses on an aperture are small and decrease with increase in the cavity held intensity as a result of self-focusing. These para meters of a four-mirror cavity are used to demonstrate that the invest igated mechanism of discrimination of the radiation fluctuations shoul d make it possible to generate a stable train of ultrashort pulses und er conditions of cw and pulsed flashlamp pumping.