Newlight Photonics Inc. – Your source for BBO, LBO, BiBO, KTP, KTA, Nd:YAG, Nd:YVO4 crystals, polarizers, waveplates ...

Newlight's Nd:YVO4 features

Low lasing threshold and high slope efficiency

Large stimulated emission cross-section at lasing wavelength

High absorption over a wide range of pumping wavelength

Large birefringence emitting polarized light

Low sensitivity to pumping wavelength variation

Basic Properties

Atomic Density	1.26x1020 atoms/cm3 (Nd doping:1.0%)
Crystal Structure	Tetragonal, space group I41/amd a=b=7.1193, c=6.2892
Density	4.22g/cm3
Melting Temperature	1825 oC
Mohs Hardness	4-5
Specific Heat @25oC	24.6 (cal/mol/K)
Thermal Expansion Coefficients (@300K)	αa=4.43x10-6/K αc=11.37x10-6/K
Thermal Conductivity Coefficients(@300K)	//C: 5.23W/m/K ⊥C: 5.10W/m/K

Optical Properties

Lasing Wavelength	1064.3nm, 1342nm
Thermo-optical Coefficient (@300K)	dno/dT=8.5x10-6/K dne/dT=2.9x10-6/K
Sellmeier Equations for Pure YVO4 crystals ( λ in µm)	no2=3.77834+0.069736/(λ2-0.04724)-0.0108133λ2 ne2=4.59905+0.110534/(λ2-0.04813)-0.0122676λ2
Refractive Index (@1064nm)	no=1.958, ne=2.168
Stimulated Emission Cross- section	25x10-19cm2 @1064nm
Fluorescent Lifetime	95 µs
Peak absorption wavelength	808 nm
Absorption Coefficient (1% Nd)	22.8cm-1 (E//c), 11.1cm-1 (E//a) @ 808nm
Intrinsic Loss	0.02cm-1 @ 1064nm
Gain Bandwidth	0.96nm @ 1064nm
Polarized Laser Emission	Parallel to the optic axis (c-axis)

Laser Properties

The Nd:YVO4 crystal has large stimulated emission cross-sections at both 1064nm and 1342nm. The stimulated emission cross-section of an a-axis cut Nd:YVO4 crystal at 1064nm is about 4 times higher than that of the Nd:YAG crystal. Although the lifetime of Nd:YVO4 is about 2.7 times shorter than that of Nd:YAG, the slope efficiency of a Nd:YVO4 laser can be very high if the laser cavity is properly designed thanks to its high pump quantum efficiency, . Table 1 lists the major laser properties of Nd:YVO4 in comparison with those of Nd:YAG. Table 2 gives the performance of a few examples of Nd:YVO4 lasers.

Table 1. Laser Properties of Nd:YVO4 in comparison with Nd:YAG

Laser crystal	Doping (atm%)	σ (x10-19cm2)	α (cm-1)	τ (µs)	Pth (mW)	Effi. (%)
Nd:YVO4 (a-cut)	1.0 2.0	25 25	23 46	90 50	30 78	52 48.6
Nd:YVO4 (c-cut)	1.1	7	9.2	90	231	45.5
Nd:YAG	0.85	6	7.1	230	115	38.6

Table 2. Diode pumped Nd:YVO4 laser output compared with that of a Nd:YAG laser ( Examples)

Crystals	Size (mm3)	Pump Power	Output (@ 1064nm)
Nd:YVO4	3x3x1	850mW	350mW
Nd:YVO4	3x3x5	15W	6W
Nd:YAG	3x3x2	850mW	34mW