Self-starting Kerr-lens mode-locked femtosecond Cr(4+):YAG and picosecond Pr(3+):YLF solid-state lasers.

We have observed true self-starting Kerr-lens mode locking in two distinct solid-state laser systems operating at room temperature by optimizing the cavity geometry to maximize the amplitude modulation with respect to the intracavity power variation. Pulses of 15 ps have been obtained from a Pr(3+):YLF laser system operating at 607 nm, and 53-fs pulses have been obtained from Cr(4+):YAG at 1.54 microm.