Apr 25 2014
Cerium is the simplest rare earth metal known. The Ce:LiSAF and Ce:LiCAF lasers are categorised as UV diode lasers. The process of generating UV light from the lasers was first developed at the Lawrence Livermore National University during the 1990s. Wavelengths produced by these lasers vary from 280 to 316nm. LiSAF is a crystal comprising of lithium, strontium, and aluminium fluoride. LiCAF comprises of lithium, calcium, and aluminium fluoride.
In the Ce:LiSAF laser, cerium is the light emitter, while lithium strontium aluminium fluoride is the crystalline host that preserves the optical characteristics of cerium. The LiSAF crystal, when doped with cerium, behaves as an optical crystal that emits lights of varying wavelengths, thus making it a tunable laser.
Ce:LiCAF is another tunable UV laser, with cerium as the light emitting source, and lithium calcium aluminium fluoride as the crystalline host. Both Ce:LiSAF and Ce:LiCAF exhibit strong energy absorption and broad tenability. Of the two lasers, Ce:LiCAF has better tunability and spectroscopic properties.
Laser Properties
| Laser Properties |
| Laser type |
Solid |
| Pump sources |
Frequency quadrupled Nd:YAG laser pumped, excimer laser pumped, copper vapor laser pumped |
| Operating wavelength |
280-316nm |
Physical and Chemical Properties
| Physical and Chemical Properties |
| Chemical formula |
Ce:LiSrAlF6 |
Ce:LiCaAlF6 |
| Crystal structure |
Trigonal |
Trigonal |
| Melting point |
766°C |
810°C |
| Thermal conductivity |
3 W/m°C |
4.58 W/m°C |
Applications
The primary application of the Ce:LiSAF and Ce:LiCAF lasers is remote atmospheric monitoring.
Some of the other applications of the Ce:LiSAF and Ce:LiCAF lasers are listed below:
- Ozone DIAL measurements
- LIDAR
- Optics research
- Detection of biological weapons in defense
Sources and Further Reading