Saturable absorbers
V:Yag
YAG crystals doped with three-valent vanadium V3+ in tetrahedral positions hint at being efficient passive absorbers for lasers operating in the 1.3 µm region. Efficient Q-switching and modelocking has been obtained with a number of active media such as Nd:YAG, Nd:YAP, Nd:KGW, Nd:YVO4 under flash-lamp and diode pumping.
V:YAG plates are available in a wide range of initial transmission values and with diameters between 2–10 mm.
| Material characteristics | |
|---|---|
| Formula | V3+:Y3Al5O12 |
| Crystal structure | cubic - la3d |
| Ground-state absorption cross-section at 1064 nm | 1.5 x 10-18 cm2 |
| Excited-state absorption cross-section at 1064 nm | 3 x 10-19 cm2 |
| Ground-state absorption cross-section at 1338 nm | 2.5 x 10-18 cm2 |
| Excited-state absorption cross-section at 1338 nm | 4.5 x 10-19 cm2 |
| Ground-state absorption cross-section at 1444 nm | 1.8 x 10-18 cm2 |
| Excited-state absorption cross-section at 1444 nm | 3 x 10-19 cm2 |
| Recovery time | 5 ns |
| Design | |
| Q-switch diameter | 2 – 10 mm |
| Q-switch thickness | according to requested initial transmission |
| Polishing | Barrel surface fine ground or polished. Perpendicular or wedged ends. Polishing according to DIN and MIL standards. |
| Coatings | Ion assisted mirrors, output couplers, antireflections |
Application example: Q-switched Nd:YAG-V:YAG microchip laser
Related download
Cr:YAG
Cr4+:YAG provides a large absorption cross section in the 0.9 - 1.2 micrometer spectral region, which makes it an attractive choice as a passive Q-switch for diode or lamp pumped Nd:YAG, Nd:YLF, Nd:YVO4, Yb:YAG lasers. Cr4+:YAG has a high damage threshold, good thermal conductivity, good chemical stability and is resistant to ultraviolet radiation.
| Material characteristics | |
|---|---|
| Formula | Cr4+:Y3Al5O12 |
| Crystal structure | cubic - la3d |
| Ground-state absorption cross-section at 1064 nm | 4 x 10-18 cm2 |
| Excited-state absorption cross-section at 1064 nm | 7 x 10-19 cm2 |
| Recovery time | 4 µs |
| Design | |
| Q-switch diameter | 2 – 12 mm |
| Q-switch thickness | according to requested initial transmission |
| Polishing | Barrel surface fine ground or polished. Perpendicular or wedged ends. Polishing according to DIN and MIL standards. |
| Coatings | Ion assisted mirrors, output couplers, antireflections |
