Sub-20 fs pulse generation from the mirror dispersion controlled Cr:LiSGaF and Cr:LiSAF lasers

We describe the state of the art of mirror-dispersion-controlled (MDC) Kerr-lens mode-locked (KLM) Cr:LiSGaF and Cr:LiSAF lasers. Such lasers, in comparison to their prism-controlled forerunners, are distinguished by high reproducibility, stability, and quality of the pulses, as well as compactness of the cavity. The shortest pulses of similar to 18 fs duration and nearly bandwidth-limited quality (Delta tau Delta nu = 0.33) have been produced in Cr:LiSGaF lasers, which have an average output power of 100 mW. In both lasers, krypton-laser was used as an ideal pump source. The effect of a red-shift of the operating wavelength (from 850 to 880 nm) when shortening of the pulse width (from similar to 50 fs to similar to 20 fs) has been observed and discussed.