Generation of 0.7–0.8 $\mu$ picosecond pulses in an alexandrite laser with passive mode locking

Picosecond pulses of 0.7–0.8 $\mu$ wavelengths were generated in an alexandrite laser as a result of electronic-vibrational transitions $^4T_2\to{}^4A_2+\hslash\omega_{\text{phonon}}$. Passive mode locking was ensured by the use of DS1 and DTTS saturable absorbers. The duration of the pulses generated using DS1 was 8 psec at wavelengths of 0.725–0.745 $\mu$, whereas the duration of the pulses generated using DTTS was 90 psec in the range 0.75–0.775 $\mu$.