Nd:YVO4 crystal - Nd:YVO4

Neodymium Doped Yttrium Vanadate (Nd:YVO₄)

Nd:YVO₄is the most efficient laser crystal for diode-pumped solid state lasers. Its good physical, optical and mechanical properties make Nd:YVO₄an excellent crystal for high power, stable and cost-effective diode-pumped solid-state lasers. Compared with Nd:YAG for diode laser pumping, Nd:YVO₄lasers possess:

• Lower lasing threshold and higher slope efficiency
• Large stimulated emission cross-section at lasing wavelength
• High absorption over a wide pumping wavelength bandwidth
• Low dependency on pumping wavelength and tend to single mode output
• Optically uniaxial and large birefringence emit strongly-polarized laser

Basic Properties:

Atomic Density: 1.26x10²⁰atoms/cm³(Nd 1.0%)

Crystal Structure: Zircon Tetragonal, space group D_4h-I4/amd

a=b=7.1193, c=6.2892

Density: 4.22g/cm³

Mohs Hardness: 4-5

Thermal Expansion Coefficient (300K): a_a=4.43x10^-6/K, a_c=11.37x10^-6/K

Thermal Conductivity Coefficient (300K): C: 0.0523W/cm/K, C: 0.0510W/cm/ K

Optical Properties: (for 1.1 atm% Nd:YVO4, a-cut)

Lasing wavelength: 1064nm, 1342nm

Thermal optical coefficient (300K): dn_o/dT=8.5 x 10^-6/K, dn_e/dT=2.9 x 10^-6/K

Stimulated emission cross-section: 25 x 10^-19cm²at 1.064μm

Fluorescent lifetime: 90ms

Absorption coefficient: 31.4cm^-1at 810nm

Intrinsic loss: 0.02cm^-1at 1064nm

Gain bandwidth: 0.96nm at 1064nm

Polarized laser emission: p polarization; parallel to optic axis(c-axis)

Diode pumped optical to optical efficiency: >60%

Sellmeier equations for pure YVO₄crystal as follows:

N_o²=3.77834+0.069736/ ( l²-0.04724) -0.010813 l²

N_e²=4.59905+0.110534/ (l²-0.04813) -0.0122676 l²

Laser Properties:

The Nd:YVO₄crystal has large stimulated emission cross-sections at both 1064nm and 1342nm. The stimulated

emission cross-section of an a-axis cut Nd:YVO₄crystal at 1064nm is about 4 times higher than that of the Nd:YAG crystal. Although the lifetime of Nd:YVO₄is about 2.7 times shorter than that of Nd:YAG. Because of its

high pump quantum efficiency, the slope efficiency ofNd:YVO4 can be very high if the laser cavity is properly designed. Table 1 lists the major laser properties of Nd:YVO₄in comparison with those of Nd:YAG.

Nd:YVO₄Specifications:

• Transmitting wavefront distortion: less than λ/4 at 633 nm
• Dimension tolerance: W 0.1 mm x H 0.1 mm x L + 0.2 mm/-0.1
• Clear aperture: > 90% central area
• Flatness: λ /8 at 633 nm, and λ /4 at 633nm for thickness less than 2mm
• Scratch/Dig code: 10/5 to MIL-O-13830A
• Parallelism: better than 20 arc seconds
• Perpendicularity: 5 arc minutes
• AR coating: R< 0.2% at 1064nm,
• AR coating: R>99.8% at 1064nm, T>95% at 808 nm
• Quality Warranty Period: one year under proper use