Our laser crystals are grown, polished, coated and measured in CRYTUR facility in Turnov.
- Czochralski crystal growth with automatic diameter control
- Grinding, cutting and polishing according to MIL standards
- Ion assisted coating of dielectric AR, HR or OC mirrors, coating and sputtering of metal mirrors
- Quality control + measurement: dopant concentration, absorption UV - IR, parallelism, flatness, surface figure S/D, double- pass interferogram, extinction ratio, output energy in puls and CW laser. Quality of each laser rod is certified by Quality certificate.
Content
Laser crystals
- Nd:YAG
- Nd:YAP
- Er:YAG & Er:YAP
- Tm:YAG & Tm:YAP
- Yb:YAG
- Cr4+:YAG saturable absorber
- V:YAG saturable absorber
Laser rod repair service
IR visualization screens
Laser optics & Coatings
Nd:YAG
CRYTUR, Ltd. grows neodymium doped yttrium aluminium garnet (Nd:YAG) crystals using the Czochralski growth method. A special protective atmosphere applied during crystal growth and post growth annealing results in a very good lasing efficiency of our crystals. Our production line covers crystal growth, machining and coating technologies.
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Our standard production of Nd:YAG laser rods includes:
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We also offer composite laser rods consisting of doped and undoped segments. These composite rods help to decrease thermal lensing and other thermal stress induced effects, particularly when used in axially diode pumped resonators.
Nd:YAG composite crystal, 5 x (4 + 8) mm, axially diode pumped with overall efficiency 29.5%
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Microchip laser design can be used for alignment-free Q-switched resonators. This compact design combines, in one piece, a cooling undoped part, an Nd:YAG active part and a passive saturable absorber segment. The dielectric mirrors are placed directly on the crystal faces. This configuration enables effective heat removal from the Nd:YAG and saturable absorber parts. |
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Nd:YAP
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Our standard offer comprises of Nd:YAP laser rods with 0.7 at. % Nd/Y for CW and 0.9 at. % Nd/Y for pulsed lasers, both of "b" orientation. Other Nd concentrations are available upon request. The threshold and slope efficiency of Nd:YAP at 1079 nm are comparable to those of Nd:YAG at 1064 nm. Rods cut along "b" axis are suited for most of applications. Linear polarization, no thermal birefringence and easy generation of 1.3 µm are the main advantages of this material. |
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The 1340 nm emission wavelength of Nd:YAP has higher absorption in water and bodily fluids in comparison with the 1319 nm emission wavelength of Nd:YAG. Taking into account the polarized output beam, Nd:YAP can be advantageously utilized in lasers with electro optic cells or harmonic generators.
Important Material Properties of Nd:YAP and Nd:YAG:
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Nd:YAP
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Nd:YAG
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| Host | Yttrium Aluminium Perovskite (YAlO3) | Yttrium Aluminium Garnet (Y3Al5O12) | |||
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| Dopant | Nd3+ | Nd3+ | |||
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| Crystal structure | orthorhombic | cubic | |||
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| Unit cell dimensions | a = 0.518 nm b = 0.531 nm c = 0.736 nm |
ak = 1.201 nm | |||
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| Refractive index (1,06 µm) |
a: 1.914 b: 1.925 c: 1.940 |
1.816 | |||
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| Thermal expansion coefficient | ||a: 9.5 x 10-6/K ||b: 4.3 x 10-6/K ||c: 10.8 x 10-6/K |
7.8 x 10-6/K | |||
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| Thermal conductivity | 0.11 W/cmK | 0.11 W/cmK | |||
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| Density | 5.35 g/cm3 | 4.56 g/cm3 | |||
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| Mohs Hardness | 8.5 | 8.25 | |||
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| Fluorescent lifetime (1% Nd) | 170 µs | 235 µs | |||
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| Linear dispersion dn/dT [10-6K-1] |
9.7 (na) | 9.86 | |||
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| Laser wavelengths | 4F3/2®4I9/2 | 930 nm | 4F3/2® 4I9/2 | 946 nm | |
| 4F3/2®4I11/2 | 1079 nm | 4F3/2® 4I11/2 | 1064 nm | ||
| 4F3/2® 4I13/2 | 1340 nm | 4F3/2® 4I13/2 | 1319 nm | ||
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Comparison of emission cross sections of Nd:YAG and Nd:YAP in dependence on its crystallographic orientation.
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| Wavelength [nm] | Emission cross section [10-19 cm2] | |||
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| Nd:YAG | 1064.1 | 3.3 | ||
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| 1318.7 | 0.95 | |||
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| 1341.9 | 0.36 | |||
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| "a" cut | "b" cut | "c" cut | ||
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| Nd:YAP | 1064.4 | 1.1 | 1.09 | 1.38 |
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| 1079.6 | 2.05 | 1.76 | 1.2 | |
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| 1399.3 | 0.69 | 0.94 | 0.78 | |
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| 1341.3 | 1.13 | 0.97 | 0.47 | |
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The main absorption line of the Nd:YAG crystal occurs at 808 nm. In case of the "b" cut Nd:YAP crystal, the peak of the absorption band is centered at 803 nm for polarization parallel to "c" crystallographic direction and 807 nm for polarization parallel to "a" crystallographic direction.
Absorption spectra of Nd:YAP (1 mm thick plate)
In the Download section you can see published results (pdf file).
Er:YAP & Er:YAG
Due to similar sizes of the ionic radii of erbium and yttrium, crystals with a high erbium content can be grown. YAG crystals highly substituted with erbium ions provide laser emission at 2.94 µm, low doped crystals at 1.6 µm wavelength.
Our standard production includes
- Er dopant concentration from 0,1 % up to 50 % of Er/Y
- Rod diameters from 2 mm up to 7 mm
- Rod lengths up to 120 mm
- Barrel surface fine ground or polished
- Perpendicular or tilted ends up to Brewster angle,
- AR coatings with R < 0.3 %
For more information see Resonantly Pumped Er:YAG and Er:YAP Lasers
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| Er:YAP | Er:YAG | |||
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| Host | Yttrium Aluminium Perovskite (YAlO3) | Yttrium Aluminium Garnet (Y3Al5O12) | ||
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| Dopant | Er3+ | Er3+ | ||
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| Dopant concentration | 1-50 at.% Er/Y | 1-50 at.% Er/Y | ||
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| Laser wavelength | 4S3/2®4I9/2 | 1.66 µm | 4I13/2®4I15/2 | 1.64 µm |
| 4I11/2®4I13/2 | 2.73 µm | 4I11/2®4I13/2 | 2.94 µm | |
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Tm:YAP & Tm:YAG
Tm doped crystals embrace several attractive features that nominate them as the material of choice for solid-state laser sources with emission wavelength around 2 µm. There is a self-quenching mechanism between the 3H4 and 3F4 levels that produces two excitation photons in the upper laser level for one absorbed pump photon. This makes the laser potentially very efficient with high quantum efficiency.
The absorption band of Tm:YAP between the 3H6 and 3 H4 levels with a peak at 795 nm is easily accessible with high power AlGaAs laser diode pumping. Also, the 4-nm wide absorption peak of Tm:YAP is broader compared to Tm:YAG, resulting in better tolerance to pump diode wavelength variations.
The emission wavelength of Tm:YAP laser depends on crystal orientation. Crystals cut along the "a" or "b" axis (ref. to Pbnm space group) are mostly used.
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| Tm:YAP | "a" cut | "b" cut |
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| Absorption peak | 794.8 nm | 793.5 nm |
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| Peak effective pump absorption coeficient | aa = 3.6 cm-1 | aa = 3.3 cm-1 |
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| Emission wavelength | 1.98 µm | 1.94 µm |
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For more information see 
Tm:YAP michrochip laser
Tm:YAG finds its application in laser radar and other atmospheric sensing applications due to its operating wavelength at 2013 nm. The absorption band peaking at 785 nm is suitable for pumping by semiconductor diodes.
Our standard offer of Tm doped YAP and YAG crystals includes:
- Tm dopant concentrations from 1 at. % up to 8 at. % of Tm/Y
- Rod diameters from 2 mm up to 7 mm
- Rod lengths up to 100 mm
- Variety of anti-reflection, partial or high reflection coatings in the range of 2 µm
Yb:YAG
Yb:YAG is well suited for high power laser applications. Its advantage is a wide pump band tolerant to pump diode wavelength variations and an excellent emission cross section.
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| Yb:YAG | ||
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| Emission wavelength | 1030 nm | |
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| Pump wavelength | 941 nm | |
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| Fluorescence lifetime | 0.95 - 1.2 ms | |
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| Emission cross section | 2.1 x 10-20 cm2 (± 10%) | |
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Our standard offer of Yb doped YAG crystals includes:
- Yb dopant concentrations from 1 at. % up to 15 at. % of Yb/Y
- Rod diameters from 2 up to 10 mm
- Rod lengths up to 100 mm
- Variety of anti-reflection, partial or high reflection coatings
Cr4+:YAG saturable absorber
YCr4+: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 the diode or lamp pumped Nd:YAG, Nd:YLF, Nd:YVO4, Yb:YAG lasers. Cr4+:YAG has high damage threshold, good thermal conductivity, good chemical stability and is resistant to ultraviolet radiation.
Cr4+:YAG can be also used for tunable lasers with output adjustable between 1350-1550 nm. It can generate ultrashort pulses when pumped at 1064 nm by a Nd:YAG laser.
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| Cr4+:YAG | ||
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| Formula | Cr4+:Y3Al5O12 | |
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| Crystal structure | cubic <100> | |
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| Thermal conductivity | 0.11 Wcm-1K-1 | |
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| Thermal expansion | 7.8 x 10-6 K-1 | |
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| Recovery time | 8.5 us | |
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| Refractive index at 1064 nm | 1.82 | |
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Our standard design of Cr4+:YAG disk
- diameter from 2 up to 10 mm
- Surface flatness - ?/10
- Surface figure - S/D 10/5
- End face parallelism - 20 arcsec.
- AR coated (85 % of aperture) - R = 0.2 %
- Partial and HR coating upon request
Nd:YAG-Cr:YAG diffusion bonded microchip lasers can be designed upon request.
V:YAG saturable absorber
YAG crystals doped with three-valence vanadium V3+ in tetrahedral positions hint at being efficient passive absorbers for lasers operating in 1.3 µm region. The 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.
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| V:YAG properties at 1.3 µm | ||
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| Ground-state absorption cross-section | 7.2 x 10-18 cm2 | |
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| Excited-state absorption cross-section | 7.4 x 10-19 cm2 | |
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| Recovery time | 5 - 22 ns | |
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| Absorption coefficient (standard V3+ concentration) | 2.2 cm-1 | |
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V:YAG plates are available in a wide range of initial transmission values and with diameters between 2 - 10 mm.
An alignment free microchip laser design consisting of saturable + active + undoped parts can be designed upon request. The dielectric mirrors can be placed directly on the crystal faces.
For more information see
V:YAG michrochip laser
Laser rod repair service
At Crytur, your laser rods can be cleaned, polished and coated with new antireflection or reflection layers.
Standard diameters of rods: 2 - 10 mm.
Flatness: l/10 at 633 nm.
Parallelism: < 10 arcsec.
Surface quality according to DIN and MIL standards.
IR visualization screens
IR- visualization screens made by CRYTUR convert the infrared laser beam to visible green spot based on two-photon absorption of laser radiation and conversion into visible light.
Size: 75 x 75 mm
Size of active area: 50 mm in diameter.
Other dimensions are available upon request
IR – SCREEN-ND:
For visualization of 1064 nm Nd:YAG laser beam. This screen is especially suitable for alignment of high power CW Nd:YAG laser resonators.
Detection limit: 0,5 W/cm2
IR – SCREEN-ER:
For visualization of laser radiation in eye-region. This screen is especially suitable for alignment of Er:glass laser resonators emitting at 1,53 microns.
Detection limit: 0,1 J/cm2