Nd:GdVO4

Nd:GdVO4


Nd:GdVO4 (Neodymium Doped Gadolinium Orthovanadate ) is a promising material for diode pumped lasers. Similar to the more well-known Nd:YVO4 crystal, Nd:GdVO4 crystal also exhibits high gain, low threshold, and high absorption coefficients at pumping wavelengths. Nd:GdVO4 has the additional advantage over Nd:YVO4 of a much higher thermal conductivity.  For CW lasing at 1.06 μm and 1.34 μm and intracavity doubling with KTP and LBO, the gadolinium vanadate have produced a higher slope efficiency or optical conversion than Nd:YVO4.

 Advantage

Large stimulated emission cross section at laser wavelength;
High absorption coefficient and wide bandwidth at pump wavelength;
Low dependency on pump wavelength;
Good thermal conductivity;
Low lasing threshold and high slope efficiency;
High laser induced damage threshold;
Strongly-polarized laser output.

Properties comparing Nd:GdVO4 with Nd:YVO4

Crystal 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(°C) 1780 1825
Thermal expansion @250C, x10-6/°C a 1.7 a 4.43
b 7.3 b 11.4
Specific heat @250C, cal/mol·K 32.6 24.6
dn / dT, x10-6/°C 4.7 2.7

Comparation of Laser Crystals

Crystal  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 0.8nm   0.45nm
(linewidth at 1064 nm)
Effectivelasercross section(emission cross section at 1064 nm) 15.6 x 10-19 cm2 7.6 x 10-19cm2 6.5 x 10-19cm2
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
Thermal conductivity, W/m/K 5.1 11.7 14
Peak pump absorption at 1% ~ 41 cm-1 ~ 57 cm-1  
doping

Capability

Common Specification
Doping 0.1%~3%
Doping Concentration Tolerance ±0.05%(atm%<1%),
±0.1%(atm%≥1%)
Orientation A-Cut ±0.5deg.
C-Cut ±0.5deg
Dimension Tolerance ±0.1mm
Perpendicularity < 10 arc minutes
Parallelism <10 arc seconds
Wavefront Distortion Lambda/6
Flatness Lambda/10
Surface Quality S/D 10-5
Chamfer 0.1mmx45°
Coating AR/HR/PR coating according to the requirement
Damage Threshold >500MW/cm2