Cr:LiSAF
Cr3+:LiSAF gain medium possesses broad emission bands in the near infrared that allow widely tunable laser operation and generation of ~10 fs light pulses via mode-locking technique. Cr:LiSAF crystals can be grown with a very low loss level (0,2%/cm) and it enables to construct high-Q-cavities, resulting in lasing thresholds as low as 2 mW and slope efficiencies above 50%. Moreover, nonlinear refractive index of Cr:LiSAF is about four times lower than Ti:sapphire, which reduces unwanted nonlinearities in ultrashort pulse generation and amplification. It’s excellent laser material with high energy storage and high slope efficiency. It’s also ideal working materials under conditions of ultra short pulse and ultra high power. Currently, Cr:LiSAF related products such as flashlight pumping and semi-conductor pumping laser have been widely used.
Parameter
Orientation | a-cut |
Parallelism | <10〞 |
Perpendicularity | 10ˊ |
Chamfer | 0.1mm@45° |
Surface Quality | 10-5 S-D |
Wavefront Distortion | λ/8 @632.8 nm |
Surface Flatness | λ/10 @632.8 nm |
Clear Aperture | >90% |
Face Diameter Tolerance | +0/-0.1mm |
Length Tolerance | ±0.1mm |
Coatings | R<1%@670nm+R<0.5%@700~1100nm on both faces |
Laser Induced Damage Threshold | >10J/cm2@1064nm, 10ns |
Crystal Structure | Trigonal |
Space Group | P31C |
Lattice Constants | a=5.08, c=10.21 Å |
Density (g/cm3) | 3.45 |
Melting Point | 766°C |
Mohs Hardness | 4 |
Modulus of Elasticity(GPa) | 109 |
Specific Heat(J/gK@298K) | 0.842 |
Thermal Conductivity(W·m-1·K-1) | 4.6(∥a), 5.1(∥c) |
Thermal Expansion(10-6K-1) | 2.2(∥a), 3.6(∥c) |
Typical Doping Level | 0.8~1.5@.% |
Absorption Peak Wavelength(nm) | 670 |
Absorption Cross-section at Peak(10-20cm2) | 5.5 |
Absorption Bandwidth at Peak Wavelength | ~100nm |
dn/dT (10-6K-1) | -4.2(no), -4.6(ne) |
Refractive Index | n=1.41 |
Laser Wavelength(nm) | 830(780-920) |
Lifetime of 4T2 Energy Level(μs) | 67 |
Emission Cross-Section(10-20cm2) | 5 |
Scatter Losses(%/cm) | <0.2 |
λ(nm) | nc | na |
846 | 1.407 | 1.405 |
670 | 1.409 | 1.407 |
423 | 1.413 | 1.412 |
290 | 1.42 | 1.42 |
266 | 1.422 | 1.424 |
- Broad absorption and emission bands
- Nonlinear refractive index is about four times lower than Ti:sapphire
- Custom crystals available upon request
- Femtosecond lasers and CPA laser systems
- Flashlight pumping and semi-conductor pumping laser
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Eberhard Riedle says
I’m looking for an undoped LiSAF crystal,
– diameter 5 mm, thickness 5 mm
or
– diameter 1/”, thickness 5 mm
or
diameter 1″, thickness 5 mm
all with optically polished faces.