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Neodymium doped Gadolinium Vanadate (Nd:GdVO4) is a promising
material for diode pumped laser. Similar to Nd:YVO4 crystal,
Nd:GdVO4 crystal also exhibits high gain, low threshold, and high
absorption coefficients at pumping wavelengths, which result from
the excellent fit of the neodymium dopant in the crystal lattice.
Nd:GdVO4 has the additional advantage over Nd:YVO4 of a much higher
thermal conductivity.
Compare
Nd:GdVO4 properties with Nd:YVO4
| - |
Nd:GdVO4, 1.2
atm% Nd |
Nd:YVO4 1
atm%
Nd |
| Melting temperature
(T©C) |
1780 |
1825 |
|
Fluorescence lifetime (t) |
95ms |
100ms |
| Stimulated emission
cross section (s) |
7.6x10-19cm-2 |
15.6x10-19cm-2(p-pol) |
|
Absorption
coefficient |
78cm-1 |
31.2 cm-1 |
| La |
0.18mm |
0.32mm |
| Threshold
power |
70mw |
78mw |
| Conversion efficiency
hs |
50% |
48.6% |
| Thermal conductivity
coefficient |
11.7w/m/k |
5.10w/m/k |
Availability:
| Nd dopant
concentration: |
0.2 ~ 3 atm% |
| Dopant
tolerance: |
within 10% of concentration |
| Diameter: |
0.02
~ 20mm |
| Length: |
0.02
~ 20mm |
| Coating
specification: |
- AR@1063nm, R< 0.1% & HT@808nm, T>95%
- HR@1063nm, R>99.8% &
HT@808nm, T>9%
- HR@1063nm, R>99.8%, HR@532 nm, R>99% & HT@808 nm, T>95%
- AR@1063 nm,
R<0.1%
|
Typical
specification and tolerance:
| Orientation: |
a-cut crystalline
direction (+/-5°C) |
| Dimensional tolerance: |
Typical: +/-0.1mm
High precision: +/-0.005mm |
| Wavefront
Distortion: |
<l/8 at 633nm |
| Surface
quality: |
better than 20/10 Scratch/Dig per MIL-O-1380A |
| Parallelism: |
< 10 arc
seconds |
| Perpendicularity: |
< 5 arc
minutes |
| Surface
flatness: |
<l/10 at 632.8nm |
| Clear
aperture: |
Central 95% |
| Chamfer: |
0.15x45o |
| Damage
threshold: |
over 15J/cm2 (rods without
coating) over 700 MW/cm2
(coating) |
Notes:
To inquire or order a finished
Nd:GdVO4 laser crystals,
please provide specifications as listed above. For most
applications, we
only need to know the following:
1)Nd-dopant concentration;
2)sizes; 3)surface quality; and 4) coating.
For special
request, please provide detailed specification for evaluation and
fabrication.
Physical and
Chemical Properties:
| Crystal Structure |
Zircon Tetragonal, space group D4h,
a=b=7.21, c=6.35 |
| Melting Point |
1780°C |
| Density |
5.47g/cm3 |
| Mohs Hardness |
Glass-like, ~ 5 |
| Thermal Expansion Coefficient |
aa=1.5x10-6/K,
ac=7.3x10-6/K |
| Thermal Conductivity Coefficient |
11.7 W/m/K <110> |
Optical Properties:
| Peak Absorption Wavelength |
808.5 nm |
| Lasing Wavelength |
912.6 nm, 1063.1 nm, 1341.3 nm |
| Crystal Class |
positive
uniaxial, no=na=nb ne=nc
no=1.9854, ne=2.1981, @1064nm
no=2.038184,
ne=2.292962, @532nm
no=1.9977322, ne=2.219864, @808nm |
| Thermal Optical Coefficient |
dn/dT=4.7x10-6/K |
| Stimulated Emission Cross-Section |
7.60x10-19cm2 , @1064 nm |
| Fluorescent Lifetime |
95 ms (1 atm% Nd doped) @808
nm |
| Loss Coefficient |
0.003 cm-1@1064 nm |
| Absorption Coefficient |
74 cm-1 @808nm (1.2%) |
| Absorption Length |
0.32 mm @808nm |
| Intrinsic Loss |
Less 0.1% cm-1 , @1064
nm |
| Linewidth |
0.6 nm |
| Polarized Laser
Emission |
p parallel to optic
axis (c-axis) |
Diode Pumped Optical to
Optical
Efficiency |
> 60% |
Sellmeier Equation
(for pure GdVO4
crystals) |
ne2=4.734369+0.1216149/(l2 -
0.0523664)
- 0.013927l2
no2=3.8987165+0.05990622/(l2 -
0.0514395) - 0.011319l2 |
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