The Cr:Y2SiO5 (Cr:YSO) crystal is an effective saturable absorber Q switch for the ruby laser, the alexandrite laser and the Cr:LiCaAlF (Cr:LiCAF) laser. Some experiments showed the Cr:YSO crystal can also be used to Q-switch the Cr:LiSrAlF (Cr:LiSAF) laser when the laser wavelength is at 880nm. Cr:YSO is a pure tetravalent chromium system. The emission lifetime of Cr:YSO is 0.7 ms at room temperature, which is long compared with the duration of the Q-switched laser pulses. Therefore Cr: YSO can be classified as a slowly relaxing saturable absorber.
Cr:YSO Crystal – Saturable Absorber Passive Q Switch for Cr:LiCAF & Cr:LiSAF Laser
The Cr:YSO can work as saturable absorber Q switch for the Cr:LiCAF laser near 780 nm, the peak of its tuning range. The theoretical simulation also shows that the Cr:YSO can be used as an effective saturable absorber Q switch for the tunable Cr:LiCAF laser over a major portion of its entire tuning range from 725 nm to 840 nm. On the other hand, the Cr:YSO had also been experimentally demonstrated to be an effective saturable absorber Q switch for the tunable Cr:LiSAF laser.
|Crystal system||Monoclinic. biaxial|
|Cr atoms/mole %||~9.7×1019/cm3|
|Main absorption peaks||390 nm. 595 nm. 695 nm and 750 nm|
|Emission spectrum||1000 nm to 1500 nm（peak at ~ 1250 nm）|
|Fluorescence lifetime at 25ºC||~0.7us|
Cr: YSO absorption curve
- High pumping rate
- Longer pulse duration
- High damage threshold
- Higher base state absorption
- 750nm wide absorption band