LiNbO3
On its excellent optical and electrical properties, LiNbO3 is one of the most important materials used for the field of optics and electronics, such as laser components, wafers for surface acoustic wave devices, wafers for integrated optics applications and doped LiNbO3 crystals for nonlinear optics (MgO
iNbO3, ZnO: LiNbO3), photo-refractive effects devices (FeiNbO3), etc.
OPO, Frequency and Quasi-Phase-Matched (QPM) Doublers
LiNbO3 is commonly applied as not only frequency doubler (wavelength > 1 mm) but optical parameter oscillator (OPO) pumped at 1.064 mm, as well quasi-phase-matched (QPM) doubler. HROPTICS supplies laser-grade LiNbO3 devices of (3-20) x (3-20) mm2 aperture and up to 60 mm length for frequency doubler and optical parameter oscillator, with high quality, large quantity and low price. Its properties show as follows:
Basic Properties
|
Crystal Structure |
Trigonal, point group 3m |
|
Lattice Parameters |
a=5.148Å, c=13.863Å |
|
Density |
4.64 g/cm3 |
|
Melting Point |
1250 °C |
|
Curie Point |
1160 °C |
|
Mohs Hardness |
5 |
Dielectric Constant |
e11/e0 = 85; e33/e0 = 29.5 |
|
Absorption Coefficient |
~ 0.1%/cm @1064 nm |
|
Thermal Conductivity |
38 W/m/°C at 25°C |
|
Thermal Expansion Coefficient |
a1=a2 =2x10-6/°C, a3=2.2x10-6/ °C at 25°C |
|
Piezoelectric Strain Constant |
d22 = 2.04 x 10-11 C/N, d33 = 19.22 x 10-11 C/N |
|
Elastic Stiffness Constant |
CE11 = 2.04 x 1011 N/m2, CE33 = 2.46 x 1011 N/m2 |
Optical and NLO Properties
|
Transparency Region |
3700 ~ 5000 nm |
|
Sellmeier Equations (l in mm) |
no2 = 4.9048+0.11768/(l2-0.0475)-0.027169l2
ne2 = 4.5820+0.099169/(l2-0.04443)-0.02195l2 |
|
Optical Homogeneity |
Dn ~ 5x105/cm2 |
|
Nonlinear Coefficients |
deff=13.6 d36(KDP) for OPO at 1064 nm
deff =14.6 d36(KDP) for SHG at 1300 nm
deff =45.0 d36(KDP) for QPM |
|
Refractive Indexes |
no ne
2.220 2.146 @ 1300 nm
2.322 2.156 @ 1064 nm
2.286 2.203 @ 632.8 nm |
Electro-optic Coefficients (pm/V) |
Low frequency High frequency
g33 32 31
g31 10 8.6
g22 6.8 3.4 |
|
Damage Threshold |
> 250 KW/cm2 at 1064 nm (10 ns) |
X-CUT
76.2 diameter*0.5---1.0mm HR-LNX0305-10
Z-CUT
76.2 diameter*0.5---1.0mm HR-LNZ0305-10
Y-CUT
76.2 diameter*0.5---1.0mm HR-LNY0305-10
127.86° Y-cut,
76.2 diameter*0.50mm HR-LNY1040305
64° Y-cut,
76.2 diameter*0.5mm HR-LNY640305
Applications for Q-switch Elements
LiNbO3 is extensively used as electro-optic modulator and Q-switch for Nd:YAG, Nd:YLF and Ti:Sapphire lasers as well as modulator for fiber optics, etc. The transverse modulation is mostly employed for LiNbO3. If a LiNbO3 crystal is used as Q-switch crystal, the light propagates in Z-axis and electric field applies to X-axis, the refractive retardation will be G = pLno3¡22V/ld. MgOiNbO3 and ZnO: LiNbO3 crystals have similar electro-optic properties to LiNbO3 but with higher damage threshold. The specifications of LiNbO3 Q-Switch Elements listed as the following table:
LiNbO3 Q-Switch Elements
|
Standard Dimension |
9x9x25 or 10x10x20mm3 (other dimension is also available upon request) |
|
Dimension Tolerance |
X & Y-axis: ± 0.1mm ; Z-axis: ± 0.3mm |
|
Wavefront Distortion |
< l/4 @633nm |
|
Orientation Accuracy |
X & Y-axis: < 10'; Z-axis: < 5' |
|
Flatness |
l/8 @632.8nm |
|
Parallelism |
10" |
|
Scratch/Dig Code |
10/5 per MIL-O-13830A |
|
Chamfer |
< 0.5 mm at 45º ± 5º |
|
AR-Coating |
R < 0.2% @ 1064 nm |
|
Electrodes |
Gold electrode on X-faces |
|
Extinction Ratio |
> 400:1 @ 633 nm for f 6mm beam) |
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Surface Acoustic Wave (SAW) Devices
LiNbO3 crystal is widely applied as an excellent acousto-optic material for surface acoustic wave (SAW) devices (such as filters, oscillators and resonators) and ultrasonic transducer due to its high electro-mechanical coupling factor, low acoustic transmission loss, stable physical and chemical properties.
HROPTICS can supply large quantities of LiNbO3 boules, as-cut or finished f3" wafers available up to 6,000~ 9,000 pieces per month with good quality and very low price. The basic specifications and typical properties for LiNbO3 SAW wafer are listed as following:
