Fig. 1. Experimental setup. DM: dichroic mirror; CM: chirped mirror; TM: third-order dispersion mirror; FL: focusing lens; H: hard aperture

Fig. 2. Curve of group delay dispersion. (a) Group delay dispersion curve of 1 mm Cr:ZnS, single CM and single TM; (b) Net round-trip group delay dispersion curve in the cavity

Fig. 3. (a) Simplified mode of resonator cavity; (b) Calculation of Kerr lens sensitivity in gain crystal

Fig. 4. Spectrum of output pulse

Fig. 5. Measurement and retrieved SHG-FROG traces of the output pulse

Fig. 6. Temporal profile retrieved from an SHG-FROG measurement

Fig. 7. Reconstructed spectrum intensity and phase distribution retrieved from an SHG-FROG measurement

Fig. 8. (a) Oscilloscope pulse trace of mode-locking pulses; (b) RF spectrum of the mode-locking pulses sequence

Fig. 9. Plot of the measured beam diameter of mode-locking pulses varied with distance