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Current location: Optics Crystals
The Czochralski method Gadolinium Vanadate doped with neodymium, Nd:GdVO4, is a promising material for diode pumped lasers. Like neodymium doped yttrium vanadate, the gadolinium vanadate exhibits a larger absorption and emission cross section compared to Nd:YAG. In fact, Nd:GdVO4 has a 7-times higher absorption cross section at 808nm and a 3-times larger emission cross section at 1.06µm than does Nd:YAG. Nd:GdVO44 has the additional advantage over Nd:YVO4 of a much higher thermal conductivity.
In each case of cw laser performance at 1.06µm and 1.34µm and intracavity doubling with KTP and LBO, the gadolinium vanadate had a higher slope efficiency or optical conversion efficiency than did yttrium vanadate.
Basic Properties:
Chemical Formula |
Gd.99Nd.01VO4 |
Dopant Concentration Nd3+, at.% |
1.0¡À 0.1 |
Crystal Structure |
Zircon Tetragonal, space group D4h-I4/amd a=b=7.212, c=6.350 |
Space Group |
I41/amd |
Optical Properties:
Lasing Transition |
4F3/2 ¨C4I11/2 |
Lasing Wavelength, nm |
1062.9 |
Emission Cross Section, (E ½ ½ c, at 1064 nm) cm2: |
7.6x10-19 |
Absorption Cross Section, (E ½ ½ c, at 808 nm) cm2: |
4.9x10-19 |
Density: |
5.48g/cm3 |
Mohs hardness: |
4.6-5 |
Linewidth: |
3 nm |
Relaxation Time of Terminal Lasing Level: |
100ms |
Absorption Coefficient, (E ½ ½ c, at 808 nm) cm-1 |
74 |
Thermal Conductivity, W/(mxK): <110> |
11.7 |
Density, g/cm3 |
5.47 |
Index of Refraction (at 1064 nm):
Wave length |
500 |
630 |
850
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1064 |
1300 |
1400 |
1550 |
no |
2.0488 |
2.01685 |
1.99490 |
1.98535 |
1.97889 |
1.97683 |
1.97410 |
ne |
2.31219 |
2.25431 |
2.21482 |
2.19813 |
2.18742 |
2.18419 |
2.18009 |
Demonstrated Performance in Diode Pumped Laser Systems
Laser Operation |
Output wavelength (µm) |
Frequency Doubler |
Slope Efficiency (%) |
Max. Optical Conversion Efficiency (%) |
cw |
1.06 |
none |
42.9 |
38.1 |
cw |
1.34 |
none |
40.2 |
n/a |
cw |
0.53 |
KTP |
n/a |
21.0 |
cw |
0.67 |
LBO |
n/a |
2.8 |
Q-switched |
1.06 |
none |
31.6 |
n/a |
Q-switched |
0.53 |
KTP |
n/a |
25.0 |
Information Regarding Neodymium Laser Host Crystals
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Nd:YVO4 |
Nd:GdVO4 |
Nd:YAG |
Laser wavelengths |
1064.3nm 1342.0 nm |
1062.9 nm ~1340 nm |
1064.2 nm 1338.2 nm |
Emission bandwidth
(linewidth at 1064 nm) |
0.8 nm |
No data |
0.45 nm |
Effective laser cross section (emission cross section at 1064 nm) |
15.6 x 10-19 cm-2 |
7.6 x 10-19cm-2 |
6.5 x 10-19 cm-2 |
Polarization |
Parallel to c-axis |
Parallel to c-axis |
unpolarized |
Radioactive lifetime (microseconds) at 1% Nd doping |
~ 100 µs |
~ 95 µs |
230 µs |
Pump wavelength |
808.5 nm |
808.4 nm |
807.5 nm |
Peak pump absorption at 1% doping |
~ 41 cm-1 |
~ 57 cm-1 |
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Thermal conductivity, W/mK |
5.1 |
11.7(Ref. 7) |
14 |
Material Properties: Comparing Nd:GdVO4 and Nd:YVO4
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Nd:GdVO4 |
Nd:YVO4 |
Crystal Structure, Space Group |
Tetragonal, I41/amd |
Tetragonal, I41/amd |
Lattice constants, nm |
a:0.721 b:0.635 |
a:0.721 b:0.629 |
Melting temperature, ¡ãC |
1780 |
1825 |
Thermal expansion @25¡ãC, x10-6/¡ãC |
a |
1.5 |
a |
4.43 |
b |
7.3 |
b |
11.4 |
Specific heat @25¡ãC, cal/mol K |
32.6 |
24.6 |
dn / dT, x10-6 /¡ãC |
4.7 |
2.7 |
Nd:GdVO4 Specifications:
Nd: Dopant Level |
1.0 atm% , 0.5% |
Wavefront Distortion |
< l/8 at 633 nm |
Scattering Sites |
invisible, probed with a He-Ne laser |
Orientation |
+/-0.5¡ã |
Dimensional Tolerance |
+0.1/-0.1 |
Surface quality |
10/5 Scratch/Dig per MIL-O-13830B |
Flatness |
l/10 at 633 nm |
Clear Aperture |
> Central 90% |
Parallelism |
< 10 arc sec. |
R/AR Coating:S1: HR@1064&532nm HT@808nm S2: AR@1064&532nm
AR/AR Coating: S1: AR@1064nm&532nm HT@808nm S2: AR@1064&532nm
Nd:GdVO4 long rods
Standard Products
Part No. |
Crystals |
Doping |
Dimension |
Coating |
GDV01 |
Nd:GdVO4 |
0.2-1% |
f3X30-65mm |
AR/AR@1064nm |
GDV02 |
Nd:GdVO4 |
0.2-1% |
f4X30-65mm |
AR/AR@1064nm |
Note: The Tm:GdVO4 or Ho:GdVO4 are available from our company.
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