Neodymium doped garnet and perovskite are the most widely used solid-state laser materials, especially suited for high output power resonators. The 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, are usually offered. 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. The 1340 nm emission wavelength of Nd:YAP has higher absorption in the water and body 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 electrooptic cells or harmonic generators.
Nd:YAP Nd:YAG
Host Yttrium Aluminium Perovskite (YAlO3) Yttrium Aluminium Garnet (Y3Al5O12)
Dopant Nd3+ Nd3+
Dopant concentration 0.7 at.% Nd/Y for cw
0.9 at.% Nd/Y for pulse		 0.8 at.% Nd/Y for cw
1.1 at.% Nd/Y for pulse
Crystal structure orthorhombic cubic
Unit cell dimensions a = 0.518 nm
b = 0.532 nm
c = 0.736 nm		 ak = 1.201 nm
Refractive index a: 1.91
b: 1.92
c: 1.94		 1.82
Thermal expansion coefficient a: 9.5 x 10-6/°C
b: 4.2 x 10-6/°C
c: 10.8 x 10-6/°C		 7.8 x 10-6/°C
Thermal conductivity 0.11 W/cm°C 0.11 W/cm°C
Density 5.35 g/cm3 4.56 g/cm3
Mohs Hardness 8,5 8,25 - 8,5
Emission wavelength in dependence on crystallographic direction
4F3/2→4I9/2 -a- 930 nm
4F3/2→4I11/2 -c- 1064 nm
-b- 1079 nm
4F3/2→4I13/2 -b- 1340 nm
4F3/2→ 4I9/2 :946 nm
4F3/2→ 4I11/2 :1064 nm
4F3/2→ 4I13/2 :1319 nm
For Nd:YAG crystal the main absorption line occurs at 808 nm. In the case of the Nd:YAP crystal, the peak of the absorption band is centered at 803 nm for E vector parallel to "c" direction and 807 nm for E vector parallel to "a" direction.
Due to the similar ionic radii of erbium and yttrium, the crystals with high erbium content can be grown. YAG crystals highly substituted with erbium ions provide laser emission at 2940 nm wavelength. Er:YAG lasers find their applications in the medical and dental areas owing to the high absorption of their emission of the wavelength 2940 nm in water and body fluids.
Er:YAP Er:YAG
Host Yttrium Aluminium Perovskite (YAlO3) Yttrium Aluminium Garnet (Y3Al5O12)
Dopant Er3+ Er3+
Dopant concentration 1-50 at.% Er/Y 50 at.% Er/Y
Crystal structure orthorhombic cubic
Thermal expansion coefficient a: 9.5 x 10-6/°C
b: 4.3 x 10-6/°C
c: 10.8 x 10-6/°C		 7.8 x 10-6/°C
Thermal conductivity 0.11 W/cm°C 0.11 W/cm°C
Density 5.35 g/cm3 4.56 g/cm3
Mohs Hardness 8,5 8,25 - 8,5
Emission wavelength in dependence on crystallographic direction
4S3/2→ 4I9/2 : 1,66 μm
4I11/2→ 4I13/2 : 2,73 μm
4I11/2→ 4I13/2 : 2,94 μm
Diode-pumped solid-state lasers based on Tm-doped crystals have gained significant interest in the last several years. One of the most interesting crystals is Tm:YAlO3, which embraces several attractive features that propose it as a material of choice for development of a solid-state laser source with emission wavelength in 1.9 mm - 2 mm region. Firstly, the absorption band between 3H6 and 3H4 levels with a peak at 795 nm is rather easily accessible with high power AlGaAs lasers diodes, on the contrary to Tm:YAG which requires 785 nm pump. Also the 4-nm wide absorption peak of Tm:YAlO3 (or Tm: YAP) is broader compared to Tm:YAG resulting in better tolerance to pump diode wavelength variations. Secondly, there is a self-quenching mechanism between 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 quantum efficiency exceeding 100%. Most of these features are common to Tm:YLF and Tm:YAP materials. The disadvantages of using Tm:YLF include upconversion and low fracture limit, which can make development of high power 1.9 mm laser using this material difficult.
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Laser crystals of slab, trigonal, composite, or micro-design are suited namely for diode pumped solid state lasers. Other crystal shapes can be produced upon request.

Composite laser rods consisting of doped and undoped segments help to decrease thermal lensing and other thermal stress induced effects.

Nd:YAG composite crystal, dia. 5 x (4 + 8) mm, pumped 
by LIMO diode HLU32F400-808 with overall efficiency 29.5%

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Your laser rods can be cleaned, polished and coated with new antireflection or reflection layers in Crytur. Standard diameters of rods: 2 - 10 mm, special size on request
Flatness < l /10
Parallelism < 10"
Surface quality acc. DIN and MIL standards
Our IR screens convert the IR-beam in the 1000 nm area to green. The screen is specially suitable for aligning of CW high power Nd:YAG resonators. Size of active area: 50 mm in diameter.
Crystals of YAG doped with three-valence vanadium V3+ in tetrahedral position suggest efficient passive absorber for lasers operating in 1.3 mm region. The efficient Q-switching and modelocking has been obtained with a number of active mediums such as Nd:YAG, Nd:YAP, Nd:KGW, Nd:YVO4 under flash-lamp and laser diode pumping.
Experimental results-Nd:YAP & Nd:YAG Laser Performance
Laser crystal Nd:YAP Nd:YAG
Emission wavelength l = 1340 nm l = 1319 nm
Output coupler reflectivity ROC = 40% ROC = 50%
Free-running pulse energy ERF = 310 mJ ERF = 120 mJ
V:YAG initial transmission T0 = 40% T0 = 60%
Modelocking train energy EMDL = 20 mJ EMDL = 10 mJ
Train envelope FWHM Dt = 10 - 15 ns Dt = 30 - 35 ns

Flash-lamp pumped Nd:YAP laser modelocked by V:YAG absorber - Train of pulses and single pulse temporal development for 47 cm resonator length.
λ = 1340 nm, E = 20 mJ, Dt < 15 ns, Single pulse rise time < 1 ns
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