Gain Crystals

II-VI is a leading supplier of laser gain crystals grown in-house, which are used in a wide variety of applications and industries. Nd:YAG, Nd:YLF and Nd:YVO4 crystals are ideal for solid state used in welding, cutting and micro-machining applications. Er:YAG crystals are used in medical lasers for aesthetic and dental applications. Our advanced growth and coating technology improves the conversion efficiency, laser damage threshold and life time.

Major Material Production Capability

■ ■ Nd:YVO4 More than 150 growth stations in Florida, USA and Fuzhou, China ■ YAG (Nd,Er,Yb,Ho,Tm) ■ Complete quality control from growth, polishing and coating ■ YLF (Nd,Pr) ■ 100 coating machines ■ Diversified coating technology from IBS, E-beam, IAD and Magnetron sputtering

WEBSITE CONTACT US © 2020 II-VI Incorporated ii-vi.com [email protected] Rev. 01 Legal notices: ii-vi.com/legal ■ ■ ■ ■ ■ Key features Nd:YVO near-infrared togreen, blue,oreven UV. (LBO,crystals BBO, orKTP)tofrequency-shift the output from the Nd:YVO emission features surpassingNd:YAG. Pumpedby laserdiodes, to middlepowerdensity. Thisismainlydue toitsabsorption and among commercial currently lasercrystals available, especially low for DopedYttrium Orthovanadate (Nd:YVO Basic Properties Mohs hardness Density Crystal structureCrystal Atomic density Physical Properties

Absorption (T%) Optically uniaxialandlarge birefringence emits polarized laser High absorptionover awidepumping wavelength bandwidth Large stimulatedemissioncross-section at lasing wavelength Low dependencyonpumpwavelength Low lasingthreshold andhighslope efficiency Figure 1. Absorption coefficient curve of0.5%dopantNd:YVO Figure 1.Absorptioncoefficientcurve 4 4 crystal hasbeenincorporatedwith high NLO crystal coefficient fordiodepumping isthemostefficientlaserhost crystal Wavelength (nm) 4

Absorption (T%) Tetragonal, spacegroup D4h Figure 2. Absorption coefficient curve of1.0%dopantNd:YVO Figure 2.Absorptioncoefficientcurve a=4.43x10-6/K, c=11.37x10-6/K ~1.37x1020 atoms/cm a=b=7.12, c=6.29 Glass-like, ~5 4.22 g/cm3 4 ) Crystals Wavelength (nm) 3 2/22/7 2/7 4 Neodymium Doped Orthovanadate (Nd:YVO4) Crystals

Optical Properties (typically for 1.1 atm% Nd:YVO4, a-cut crystals) Lasing wavelengths 914nm, 1064nm, 1342nm dna/dT=8.5x10-6/K, dnc/dT=3.0x10-6/K Stimulated emission cross-section 25.0x10-19cm2 @1064nm Fluorescent lifetime 90us @808nm, (50us @808nm for 2atm% Nd doped) 31.4cm-1@808nm Absorption length 0.32mm @808nm Intrinsic loss Less than 0.1% cm-1@1064nm Gain bandwidth 0.96nm (257 GHz) @1064nm Polarized laser emission p polarization, Parallel to optic axis (c-axis) > 60% Positive uniaxial, no=na=nb, ne=nc, no=1.9573, ne=2.1652, @1064nm Crystal class no=1.9721, ne=2.1858, @808nm no=2.0210, ne=2.2560, @532nm Sellmeier equation no2=3.77834+0.069736/(λ2-0.04724) - 0.0108133λ2

(for pure YVO4 crystals, λ in um) ne2=4.59905+0.110534/(λ2-0.04813) - 0.0122676λ2

Specifications of Nd:YVO4

Parameter Unit Atm% 0.1~4.0 tolerance within 10% of concentration Wavefront distortion/8@633nm (length < 10mm) Transmitting Wavefront distortion/4@633nm (length < 20mm) Dimension tolerance mm (W±0.05) × (H±0.05) × (L±0.05) Clear aperture > 90% central area Flatness < λ/8@633nm Surface quality (scratch/dig) Better than 10/5 MIL-O-13830A < 10 (length < 10mm), Parallelism arc second < 20 (10mm < length <20mm) Perpendicularity arc minute < 12 Orientation deg. < ±0.5 Coating type Adhesion and durability Meets MIL-C-48497A standards Quality warranty period One year under proper use

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2/23/7 Yttrium Aluminum Garnet (YAG) Crystals

Utilizing the proven Czochrolski technique, II-VI produces YAG crystals with a number of including Nd, Ho, Yb, Tm, Cr, Ce and Er. II-VI utilizes the highest quality materials, precision growth systems and state-of-the-art, real-time metrology to produce industry-leading YAG materials.

Options include:

■ Fast turn over for new and customer supplied YAG rods ■ Dopant concentrations: Nd 0.4% to 1.20%, Er:50%, Ce: 0.05% ■ Standard rod sizes: 2 to 25.4mm diameter and lengths 1 to 220mm ■ Custom geometries available upon request ■ Flat, wedge and radius configurations are available on all rods ■ High damage threshold coatings are available on all rods: AR, PR, HR, and Dual Wavelength

Key Features

■ High gain ■ Good thermal conductivity and thermal shock characteristics ■ Low threshold ■ Mechanical strength ■ High efficiency ■ High optical quality ■ Low loss at 1064nm ■ Material characteristics that allow for various modes of operation (CW, pulsed, Q-switched, mode locked)

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2/24/7 Yttrium Aluminum Garnet (YAG) Crystals

Basic Properties

Chemical formula Y3Al5O12 Crystal structure Cubic Lattice constant 12.01Å Melting point 1970°C Density 4.5g/cm3 Reflective index 1.82 7.8x10-6 /K<111>，0 - 250 ， 14W/m/K, 20°C Thermal conductivity 10.5W/m/K, 100°C Mohs hardness 8.5 Stimulated emission cross section 2.8x10-19cm-2 0.003cm-1 @ 1064nm Linewidth 0.6nm Radiative lifetime 550μs

Specifications of Nd:YAG Rod

Parameter Unit Material YAG Dopant concentration % 0.4~1.3 with tolerance +/-0.05% Transmitting wave front distortion λ/4 to λ/10@633nm per inch in length depending on the diameter Diameter mm +0.0,-0.025 Length mm +/-0.5 Flatness < λ/10@633nm Surface quality (scratch/dig) Better than 10/5 MIL-O-13830A Parallelism arc second < 10 Perpendicularity arc minute < 5 Ground Chamfer mm 0.13 FW@45° Typical Coating type According to the requirement of the client Quality warranty period One year under proper use

Applications

■ Nd:YAG can produce blue laser with the frequency-doubling of 946nm ■ Nd:YAG can be operated in a very high power laser up to kw level at 1064nm ■ Nd:YAG can be Q-switched with Cr4+YAG directly ■ Nd:YAG can be used for high power green lasers for SHG at 1064nm

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2/25/7 Lithium Yttrium Fluoride (YLF) Crystals

II-VI houses a dedicated area for YLF growth capability that produces a variety of gain materials covering the spectrum from UV to mid-IR, including the list below. For dopant concentration and material availability please contact us.

Options include:

■ Fast turn over for new and customer supplied YLF rods ■ Dopant types: Nd:YLF, Ho:YLF, Tm:YLF, Ce:YLF, Pr:YLF, Er:YLF, Eu:YLF, Tb:YLF, Dy:YLF, Pure YLF ■ Standard rod sizes: 2 to 10mm diameter and lengths 1 to 80mm ■ Custom geometries available upon request ■ Flat and wedge configurations are available on all rods ■ High damage threshold coatings are available on all rods: AR, PR, HR, and Dual Wavelength

Key Features

■ High gain ■ Low threshold ■ High efficiency ■ Low loss at 1064nm ■ Good thermal conductivity and thermal shock characteristics ■ High optical quality

II-VI grows Nd:YLF crystals using the Czochralski method. The use of high quality materials for crystal growth, whole boule interferometry and precise inspection of scattering particles in crystals using He-Ne laser assures that each crystal performs well.

Basic Properties

Optical Properties Transparency range 180-6700nm 1.8×10-19/cm2(E ∥ c) at 1047nm Peak stimulated emission cross section 1.2×10-19/cm2(E ⊥ c) at 1053nm Spontaneous fluorescence lifetime 485 µs for 1% Nd doping Scatter losses <0.2%/cm α= 10.8cm-1 (792.0 nm E ∥ c) for (1.2% Nd) α= 3.59cm-1 (797.0 nm E ⊥ c) 1047nm ( ∥ c, a-cut crystal) Laser wavelength 1053nm( ⊥ c, a or c-cut crystal)

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2/27/7 Lithium Yttrium Fluoride (YLF) Crystals

Physical Properties Chemical formula LiY 1.0-x Nd x F4 Space group I41/a Nd atoms/cm3 1.40 X 1020 atoms/cm3 for 1% Nd doping Modulus of elasticity 85 GPa Crystal structure Tetragonal Cell parameters a=5.16 Å , c=10.85 Å Melting point 819℃ Mohs hardness 4~5 Density 3.99 g/cm3 Thermal conductivity 0.063 W/cm/K 0.79 J/g/K 8.3×10-6/k ∥ c 13.3×10-6/ k ⊥ c

Index of Refraction dn / dT Wavelength (nm) no ne 262 1.485 1.511 Wavelength (nm) E ∥ c E ⊥ c 350 1.473 1.491 436 -2.44×10-6/℃ -0.54×10-6/℃ 525 1.456 1.479 578 -2.86×10-6/℃ -0.91×10-6/℃ 1050 1.448 1.470 1060 -4.30×10-6/℃ -2.00×10-6/℃ 2065 1.442 1.464

Specifications of Nd:YLF Rod

Parameter Unit Material Nd:YLF Dopant concentration atm% 0.4~1.2 Transmitting wave front distortion λ/4 to λ/10@633 nm per inch in length depending on the diameter Diameter mm +0.0,-0.025 Length mm +/-0.5 Flatness < λ/10@633nm Surface quality (scratch/dig) Better than 10/5 MIL-O-13830A Parallelism arc second < 10 Perpendicularity arc minute < 5 Ground Chamfer mm 0.13 FW@45° Typical Coating type According to the requirement of the client Quality warranty period One year under proper use

Applications Nd:YLF can emit 1053, 1047, 1313, 1324 and 1370nm wavelength lasers. Compared to the Nd:YAG crystal, it has higher pulse energy and polarization output at low repeat frequency (<2KHz). In addition, it has a smaller focus lens effect and wider fluorescence. 7/7

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